New EnglandWildFlowerbackstage.newenglandwild.org/resources/conservation...2–New England Wild Flower W ith all the hungry, slavering, assiduous little insects out there, waiting

NewEnglandWild FlowerConservation Notes of the New England Wild Flower Society

Plant and Insect Interactions

MakingConservation

PossibleThe New England

Wild FlowerSociety’s

Permanent ConservationEndowment

Fund

The New England Wild Flower Society

is committed to protecting native plants

and their habitats. Pleaseconsider sharing in ourcommitment. For infor-mation, call the Society’s

development office at508-877-7630, extension 3801.

Praying mantis (Mantis religiosa)

Plant and Insect InteractionsGardeners tend to have a “love-hate” relationship with insects. We cringe whenwe watch our laboriously hand-raised plants shrivel under a siege of aphids; wepluck voracious Japanese beetles one by one off our roses; we struggle with theethical dilemma of spraying to arrest a gypsy moth outbreak. Do we pay as muchattention, though, to the daily activities of the good guys—the gorgeous butter-flies that pollinate our prize flowers or the praying mantises that eat the insectsthat would eat our plants? It’s the “little things that run the world,” in the words of entomologist E. O. Wilson, and this issue of Conservation Notes celebrates the scores of miraculous and largely unseen partnerships betweeninsects and plants.

The articles in this issue delve deeply into the ecology of plants and insects (andother many-legged friends) with a particular focus on New England. We’vetapped a host of talented insect experts from around the country, who, throughscientific studies, painstaking field observations, and skilled photography, reveal a wealth of relationships that take place on a tiny scale but have landscape-scaleeffects. Insects and plants have coevolved for hundreds of millions of years; infact, the diversity and success of seed plants owe much to insects. Insects areoften the overworked, underpaid vassals of plants: Dispersing their seeds, movingtheir pollen about (even under water!), strengthening the flavors and medicinalqualities of edible plants by stimulating chemical defenses, and even—in the caseof carnivorous plants—feeding plants themselves. A rich gallery of photographsof insects doing what they do best accompanies each story. Look for profiles of rare insects of New England, many of which have been discoveredonly in the past few years of sleuthing. We present tips for attracting insects using diverse plantings and a backyard experiment to discover elusive night fauna using a sugary lure.

This issue also coincides with the BIG BUGS sculpture exhibitionand web-of-life extravaganza at Garden in the Woods. Artist DavidH. G. Rogers fashioned gigantic sculptures of insects and spidersfrom found forest materials such as red cedar, black locust, blackwalnut and willow. Gracing the garden from July 17 to October17, 2004, these really BIG bugs are the centerpiece of explorationand celebration.

We hope that by exploring this world and coming to Garden in the Woods tocommune with a 15-foot-tall beetle or two, you’ll begin to cultivate the “love”end of that relationship you’ve had with bugs.

Elizabeth Farnsworth, Ph.D., NEWFS Senior Research Ecologist,and Greg Lowenberg, Ph.D., NEWFS Director of Education

2 Why the World Is Greenby Elizabeth Farnsworth

4 The Mating Gameby David Giblin

8 Plant HerbivoreInteractionsby Greg Lowenberg

12 Antsby Henry Art

14 Insects Raise Some Galling Questionsby Warren G. Abrahamson

16 Killer Plants of NewEngland and Beyondby Elizabeth Farnsworth

18 The Enemy of MyEnemyby Christopher W. Leahy

20 Life Down Underby Bruce C. Wenning

22 IPM: Integrated PestManagementby Robert D. Childs

24 Ecological Landscapingby Cheryl Lowe

26 Tiny Destroyer ofMighty Forestsby Pam Thomas

28 A Daydream Journeyby Mike Nelson

32 Interviews with Insect Expertsby Bonnie Drexler

36 References

New England Wild Flower

Conservation Notes of the New England Wild Flower Society

Volume 8, No. 2, 2004

This publication was made possible through the generosity of Jackie and Tom Stone, The Millipore Foundation, andmembers and friends of the NewEngland Wild Flower Society.

Spicebush swallowtail (Papilio troilus)on red clover (Trifolium pratense)

2–New England Wild Flower

With all the hungry, slavering, assiduous littleinsects out there, waiting in the wings, so tospeak, to devour every last plant, you’d think

the plant world would be reduced to a leafy pile of frass(bug poop!) by now. Plants are sorely outnumbered.About 300,000 flowering species face the piercing, suck-ing, and chewing advances of some 3,000,000 or moreinsect species. This unsettling realization leads to the ques-tion: “Why is the world green?” And the answer is: Theworld is green because plants have found ways—fromtrickery to chemicals to body-armor—to outsmart the bestof the bugs. The world is green because plants have alsoco-opted insects into facilitating their own reproduction,dispersing their seeds, and even protecting them againstother, nastier herbivores. The world is also green becauseinsects face their own threats and limits to growth fromcompetitors, predators, and parasites, about which you’lllearn more as you read on.

Plants and insects have formed complex partnershipsthrough an arduous, sometimes uneasy, evolutionarycourtship. While the stories to follow will celebrate the fab-ulous and fanciful outcomes of all this trial-and-error innatural selection, this essay focuses on the process of evolu-tion itself and on some of the recent scientific research thatilluminates how this dance has played out over hundreds ofmillions of years. In fact, insects and plants have madesome of the best model systems to date for elucidating theprocess of coevolution in nature.

There is solid evidence that insects and plants have helpedeach other diversify into the abundance of species we see

today. The most species-rich group of insects in the world,the beetles, have been plant-feeders since shortly after thedawn of their own history some 230 million years ago.The weevil (Curculionids) and the potato beetle(Chrysomelids) families found plants particularly good eat-ing, and had a diverse smorgasbord of species to choosefrom. As the angiosperms began to proliferate in theCretaceous years (144 to 65 million years ago), the beetlesfollowed suit in short order, colonizing new types of hostplants, adapting locally to the unique chemical flavors ofeach one. Research reconstructing the family tree (phy-logeny) of beetles by Dr. Brian Farrell of HarvardUniversity has demonstrated that these two beetle lineagesbranched out explosively as the angiosperms diversified.Meanwhile, some of the earliest flowers (resembling modern-day magnolias) evolved ways to attract insect visitors as polli-nators, offering large floral displays and nectar rewards to thebeetles, leading to further divergence of flower form and thusnew plant species. Some of the very same players from thattime pursue these interactions even into the present day.

While these laboriousreconstructions of the pastare suggestive, they remainlargely theoretical until“rock-solid” evidence forthese early partnerships isunearthed from directobservation of fossils. Infact, the Jurassic-agedKaratau beds of Kazakhstanyield up magnificent fossils

Hornet fossil

Why the

Klamath weed beetle (Chrysolina quadrigemina) on St. John’s wort (Hypericum sp.)

World Is Greenby Elizabeth Farnsworth, Ph.D.,

NEWFS Senior Research Ecologist

“Plants and insects have formed complex partnerships throughan arduous, sometimes uneasy, evolutionary courtship.”

of insects in plants, confirming that many of these hypoth-esized relationships are truly ancient. Likewise, the 97 mil-lion-year-old Dakota Formation of the Midwest, studiedby Dr. Conrad Labandeira of the Smithsonian Institution,shows that beetles weren’t the only insects that realizedthey were onto a good thing. Leaf miners (moth larvaethat burrow characteristic tunnels into foliar tissue) aregorgeously preserved in the fossil leaves of earlyangiosperms. Speciation of the miners and other leaf-eatersreally took off when these insects began to exploit primi-tive broad-leaved plant species, which were surely morenutritious than tough, needle-leaved conifers. Shortlythereafter in geological time, deciduous leaves suddenlybecame more common among angiosperms. Is this coinci-dence or the result of strong natural selection toward dis-posable leaves that shed herbivores handily when they drop?

Evolution is full of false starts, failed experiments, andreversals. Some types of insect associations have appearedand reappeared multiple times in history. Take the exampleof insect “agriculture,” whereby insect “farmers” plantfungi in their nests to help digest plant material or to neu-tralize plant defensive chemicals. This trait has appearedand stuck among the leafcutter ants, tiny ambrosia beetles,and certain termites—interestingly, all insects that showfeatures of sociality. Perhaps agriculture spurs the develop-ment of societies in insects as readily as it has in humans.

Today, we can still watch coevolution in action. Indeed,the nature of interactions between plants and insects canshift swiftly over time and space. Recent studies by Drs.John Thompson and Brian Cunningham in the northwestU.S. have shown that the same moth species that is a faith-ful pollinator of a plant in one region can function morelike a parasite on the same plant species a few miles away, ifthe pressures of natural selection vary over space andimpose novel demands on the partnership. These shifts inbehavior and plant response cause even nearby populationsto diverge within a few generations, and incipient specia-tion begins. Thus, it isn’t difficult to envision how thewonderful myriad of insects and plants—strange but loyalbedfellows to be sure—have evolved and will continue togenerate new forms and combinations in a green world, ifwe let them.

Conservation Notes of the New England Wild Flower Society–3

Leaf miners on columbine (Aquilegia sp.)


Two members of the opposite sex find one anotherusing one or more of their senses (e.g., sight, smell,touch). This is the way mating begins for many

groups of organisms, but for the angiosperms (floweringplants) things are different. The majority of flowering plantspecies require intermediaries from the animalkingdom—such as bees, butterflies, and other insects, col-lectively known as pollinators—for successful mating. Thisdynamic relationship, which began millions of years ago,has contributed to the diversity of floral forms and colorsthat fill the natural world and inspire us to garden. NewEngland’s 2,000 native plants display the range of floralinnovations and engineering marvels that have evolved fromthe extraordinary association between flowering plants andtheir pollinators.

THE START OF A BEAUTIFULPARTNERSHIPEvidence suggests that plant-pollinator interactions origi-nated approximately 300 million years ago with weevils(beetles) transferring pollen between male and femalecycads (tropical gymnosperms). Despite this early innova-tion, insect pollination never spread in this lineage of vas-cular plants, and today nearly all gymnosperms, such as pine,juniper, larch, yew, spruce, and fir, are wind-pollinated.

Current fossil data indicate that the angiosperms arose atleast 130 million years ago, and animal-mediated pollina-tion probably developed soon after. Today, there are

approximately 270,000 species of angiosperms, and a sub-stantial portion of this diversity can be attributed to theevolutionary changes in flower color, flower shape, and nec-tar production encouraged by plant-pollinator interactions.

The alliance between plants and pollinators persists becauseit brings mutual benefits. Pollinators visit flowers to obtainpollen, nectar, and oils to fuel their activities, feed theiroffspring, or attract mates. Plants benefit when the pollinators transfer pollen between flowers of the samespecies, which for many is a necessary part of their reproductive process.

FLOWERS EVOLVED WITH THEIRPOLLINATORSA general evolutionary trend has been from large, openflowers with many individual parts, to specialized flowerscontaining fewer, fused parts. One possible explanation forthis trend is that complex flowers arose through a processof coevolution, which favored increased efficiency in polli-nation and specialized pollinators with high fidelity to par-ticular plant species. Pollinators are most efficient whenthey obtain maximum rewards for the energy they invest inforaging; plants achieve maximum reproductive potentialwhen the greatest amount of pollen is transferred betweenflowers belonging to the same species. Two woody speciesfound growing at Garden in the Woods illustrate this con-cept of pollinator efficiency nicely.

by David Giblin, Ph.D., University of Washington’s Burke Museum

The Mating Game:The Mating Game:For Plants, It Takes Three


Magnolia virginiana (sweet bay) belongs to one of theoldest plant families, Magnoliaceae. The musk-scentedflowers have six to nine large white petals, many thickanthers that produce copious amounts of pollen, and alarge central axis containing numerous pistils. These mas-sive, open-architecture flowers permit visitors of all types,including beetles that typically eat the anthers, to getpollen smeared on their bodies while feeding, and transferthe pollen the next time they visit another flower. Whetherthe beetle will visit a sweet bay plant next is unpredictablebecause beetles tend to visit any flower that they can getinto. The lack of precision in this system is evident fromthe abundant pollen amounts that are produced to com-pensate for those grains eaten or wasted when they aredelivered to a flower of a different species. Nevertheless,existence of Magnoliaceae members over tens of millions ofyears is evidence of the long-term success of this strategy.

Cercis canadensis (redbud) belongs to the Fabaceae(legumes), a more recently evolved family. Its lightly fra-granced flowers have five purplish-pink petals that inter-lock to enclose the 10 anthers and single pistil. This archi-tecture deters indiscriminate visitors because access to nec-tar inside the flower requires manipulation of the petals.Bees are the primary pollinators of redbud because theyare strong and agile enough to handle such flowers. Overtime, bees learn that they will be rewarded for theirefforts, and therefore continue to visit redbud flowerswhile they bloom. When a bee penetrates the petals of aredbud flower, it triggers the release of anthers that daub

Redbud (Cercis canadensis)

Sweet bay (Magnolia virginiana) and diagram of common flower parts

Bee pollinating pink turtlehead (Chelone lyoni)


pollen on the bee’s torso. The redbud’s petal arrangementis altered by the sprung anthers, and this change informsother bees that the flower has already been entered. Redbudplants enhance pollinator efficiency by letting pollinatorsknow when a flower’s rewards are no longer available.

ATTRACTING THAT “SPECIAL SOMEONE”Some plant species produce a deceptive aroma to attractpollinators. Red and white trillium blossoms are synony-mous with spring at Garden in the Woods. Anyone whohas experienced the fetid, rotten-meat smell of blood redT. erectum flowers (stinking Benjamin) won’t be surprisedto learn that plant’s primary pollinators are flies and bee-tles that deposit their eggs on dead flesh. Mistaking theplants for the dead animals they mimic, these insects trans-fer pollen from anther to stigma.

To understand how pollinator behavior can contribute toangiosperm speciation, researchers examine closely relatedplant species that share a similar geographic distribution,but have distinctly different floral shapes. An outstandingexample of this is provided by two Lobelia species thatflower in wet habitats in late summer.

Lobelia siphilitica (great lobelia) has fused blue petals thatform a broad tube terminated by an upper and lower lip,and the flowers are pollinated by bumblebees. Theenlarged lower lip of the great lobelia serves as a landingsurface that bumblebees cling to while sipping nectar.Lobelia cardinalis (cardinal flower) on the other hand, hasbrilliantly red, narrowly tubular flowers with a less substan-tial lower lip. Hummingbirds are drawn by the brightcrimson coloring, and, because they hover while drinkingnectar, do not require a perching surface. It is importantto note that bumblebees exhibit a strong affinity for bluelight, but have poor perception for the color red.

Thus, pollinators with very different tastes can lead tostrong natural selection for diverse flower forms evenamong closely related plant species.

REMARKABLE FLORAL “ENGINEERS” Some plant species have evolved flowers with physical fea-tures that prevent self-pollination. Sarracenia purpurea(purple pitcher plant), which grows in New England bogs,is well-known for its carnivorous habits. Highly modifiedleaves form “pitchers” that trap and digest insects. A lesswell-known characteristic of this plant is the entrance-door, exit-door flowers created by the placement of thepetals relative to the pistil and anthers. The pendulousstrap-like petals are arranged alternately with the stigmaticlobes of the inverted-umbrella-like pistil. The petals serveas a physical barrier, ensuring that the only entrance to theflowers’ interior is over the stigmatic lobes where pollen isscraped from the bees’ bodies. Visiting bees then rubagainst the anthers at the base of the pistil while sippingnectar, and thereby the flower places some of its ownpollen on the visitors before they leave. The process is

Great lobelia(Lobelia siphilitica)

Cardinal flower(Lobelia cardinalis)

Stinking Benjamin (Trillium erectum)

Purple pitcher plant(Sarracenia purpurea)

Butterfly weed(Asclepias tuberosa)


repeated, and cross-pollination achieved, when bees visitflowers on adjacent plants.

Asclepias tuberosa (butterfly weed), a plant that grows insandy, well-drained areas of New England, shows equallycomplex floral engineering. Each of the flower’s fiveanthers packages its pollen into two pollinia (pollen sacs)suspended from a central point—imagine two peapodshanging from a small button. The pendant pollinia arepicked up by the legs of nectar-seeking bees and butter-flies. When the pollinator forages on other butterfly weedflowers, one or both of the pollinia, filled with hundreds ofpollen grains, are inserted by chance into stigmatic slitsthat ring each flower. The complexity of this arrangementreduces the probability of successful pollination, but alsoreduces the likelihood of receiving mixed loads of pollenwhich can result in fruit abortion. Next fall, observe howfew pods each butterfly weed plant produces, but howmany seeds are found in each pod.

Sometimes, pollen is dispersed from a secondary structureother than the anther. This is one of the diagnostic charac-teristics of the Campanulaceae (harebell) and Asteraceae(composite) families. My favorite example is found inCampanula rotundifolia (harebell). The maturing stigmaand style elongate through a ring of inward-openinganthers. The exterior stigmatic surface is covered in hairsthat brush the pollen out of the anthers on their way past.Pollen is then presented to pollinators on these specialhairs. Stimulation of these hairs by pollinators (typicallybees foraging for nectar at the base of the style) causes thehairs to retract. This retraction induces the stigmas to openand become receptive to pollen. The more that hair stimula-tion occurs, the faster the hairs retract and the sooner thestigmas open. In effect, these flowers have “pollinator-o-meters” that guide the transition from the flower’s malephase (pollen dispersal) to its female phase (pollen receiving).

THE CONSERVATION IMPERATIVEAs humans, we are the unintended beneficiaries of the100-million-year-old association between flowering plantsand their pollinators. The importance of flowers to us is

undeniable: They adorn our living and gathering spaces,commemorate our celebrations, and, when fertilized, theyprovide many of the foods that nourish us. In NewEngland, flowers signal the end of the long, cold wintersthat define the region, and the work of pollinators pro-duces the blueberries, apples, and cranberries that we enjoy in summer and fall. The living collections at Gardenin the Woods and the many protected natural areas in our region provide the opportunity to appreciate, learn about, and contemplate flowers and pollinators—an important contribution to the preservation of this mostremarkable relationship.

Like our native flora, pollinators are also in need of conser-vation. The application of broad-spectrum insecticides killspollinators as effectively as targeted pest species, and habi-tat destruction eliminates suitable sites for pollinators tonest and reproduce. The Coevolution Institute(http://www.coevolution.org/) coordinates an interna-tional (Canada, Mexico, U.S.) effort in pollinator conser-vation, and currently has the support of over 40 profes-sional, academic, and nonprofit organizations.

It is important to recog-nize that pollination is notsynonymous with eitherfertilization or reproduc-tion. Pollination is thedeposition of pollen onthe surface of a flower’sstigma, which may or maynot result in successful fer-tilization; fertilization isthe union of two gametes(e.g., egg and sperm); andsexual reproduction is thegeneration of offspringfollowing fertilization.

David Giblin was aHorticulturist at Garden in the Woods from1988–1991. In 1997, heearned an M.S. degree inForestry from theUniversity of Washington,and in 2001 received hisPh.D. in Biology from theUniversity of Missouri-Columbia. He is currentlyHerbarium CollectionsManager at the Universityof Washington’s BurkeMuseum.

Four pollen grains have germi-nated on this stigma (upperright). Fluorescent dye revealspollen tubes growing insidethe style toward the flower’sovary where sperm will bereleased (lower left, not shown).

Harebell (Campanula rotundifolia)


Plant-HerbivoreInteractionsIf you think plants are passive, think again!

by Greg Lowenberg, Ph.D., NEWFS Education Director

Look closely at the foliage of plants in your garden orlocal natural area, and you will often see some dam-age to leaves, stems, flowers, fruit or seeds caused by

one or more kinds of insects. If our beloved plants couldtell their personal stories, each vignette would have all theelements of a suspense novel—attacks, counterattacks,feeding frenzies, love, sex, bribery, poisonings, and grandlarceny, not to mention protection rackets, secret immu-nizations, chemical defenses, and murder. Yes, our nativeNew England flora lives in a tough neighborhood, sharingspace with thousands of herbivorous insect species. Butplants are not merely innocent victims. Over countless gen-erations, they have evolved a surprising variety of ingeniousmechanisms to cope with hungry insects and other ani-mals. And like a classic arms race, insect herbivores havedeveloped countermeasures, some of them highly effective.A bug’s gotta’ eat, right?

You’ve probably heard the story of the monarch butterfly’scaterpillar, which feeds on milkweed—plants whose foliagecontains powerful poisons called cardiac glycosides, or car-denolides. The chemicals don’t harm the monarch, butrender both caterpillar and adult butterfly highly distasteful

to bird predators. Though they don’t deter the monarchcaterpillars, cardiac glycosides do work as a deterrentagainst most other insect herbivores. Only a few insectspecies, like the monarch, have the appropriate enzymes intheir guts to help deactivate such chemicals or isolate andsequester the nasty compounds into certain body tissues sothey don’t interfere with cellular metabolism and theinsect’s normal growth and development. In the case of theadult monarch, the poisons are stored in the butterfly’s high-ly vulnerable outer wing. The strategy isn’t always effective; atachinid fly (Zenillia adomsonii) can sequester the monarchcaterpillar’s cardenolides into parts of its own body, allowingit to resist the poison, too, and attack with impunity.

Insects may be highly specialized, dependent on one or afew plant species, and thus develop unique behaviors tohelp them locate the appropriate hosts. Other insects havethe ability to feed on a large variety of plants. These gener-alist insects often have “multifunction oxidase systems,” afancy way of saying they can chemically defuse many if notall of the plant compounds that might otherwise limit theirfeeding or growth.

Moth floating in purple pitcher plant (Sarracenia purpurea)


Herbivorous insects are crucial links in New England’s ter-restrial and aquatic food webs. Given the reproductivepotential of most insects, why haven’t they consumed allthe planet’s leafy vegetation? As was asked in the earlier arti-cle, why indeed is the world still green? Herbivorous insectpopulations are controlled by predaceous insects, mammals,birds, diseases, and parasites. And truly, plants don’t alwaystaste so good, even to an insect. Plants successfully defendthemselves most of the time; and when they sustain damage,they often have amazing powers of regrowth.

How Do Bugs Eat Plants? Let Us Count the WaysInsects find ways to make use of every part of a plant, usingmany different feeding techniques: gall-making (wasps,flies), seed predation (beetles, wasps, moths), root-feeding(beetles, cicadas), skeletonizing (moths), rasping-sucking(thrips), piercing-sucking (aphids), nectar-robbing (bees),stem-boring (beetles), and leaf-chewing (many groups).

Consider the case of the eastern red oak (Quercus rubra)in New England. With its long life, the tree cannot escapeits herbivores like some short-lived plants whose popula-tions are ephemeral and move around the landscape. Theoak is a sitting target, and indeed has built up a large com-munity of feeding insects.

● The oak skeletonizer (Bacculatrix ainsliella) emergesfrom a cocoon in the spring and lays its eggs on recentlyexpanded leaves. The moth’s larva feeds by making tinytunnels, or “mines,” between the leaf’s upper and lowersurface. Later, it emerges to feed on the outside of the leaf,avoiding the tough veins.

● The oak apple gallmaker (Amphibolips confluenta) laysits eggs as young oak leaves are being formed, stimulat-ing the tree to form a fibrous mass (or gall) around theemerging larvae. This larval wasp feeds inside the galland later bores an exit hole (see galls article on page 14).

● The oak leafroller (Archips semiferana), another moth,feeds on young leaves after first rolling up or foldingleaves together for protection. When a larva completesdevelopment, it spins a cocoon in the rolled leaf or in abark crevice.

● The red oak borer (Enaphalodes rufulus), a beetle, laysits eggs in July and August on the bark. The larva feedsby mining under the bark during the first year, and thentunnels into the wood the second year.

● The broad-necked root borer (Prionus laticollis), anoth-er beetle, deposits hundreds of eggs in the soil in earlysummer. The larvae emerge and burrow through the soilwhere they chew on oak tree roots for three to five years.

● Each summer, long-snouted acorn weevils (Curculiospp.) emerge from the ground. After mating, the femaledrills a hole into a developing acorn with her snout,depositing two to four eggs inside. The grub-like weevillarvae hatch and feed on the developing nut for a fewweeks. After the acorn drops, an acorn weevil chews itsway out of the acorn, and tunnels into the ground,where it lies dormant for several years.

● After the acorn weevil abandons its home, the acornmoth (Valentinia glandulella) is ready to take over theweevil’s former larder. The female moth lays an egg nearthe opening left by the weevil. Once the caterpillarhatches, it crawls inside through the weevil’s exit hole.The larva spends the winter inside the acorn on theground, and moves out in the spring to develop into anadult moth.

● Oaks and several other tree species are hosts to a recentNew England invader, the European winter moth(Operophtera brumata). Adult moths mate in early win-ter, and the wingless female lays eggs on twigs. The“inchworm” caterpillars hatch in the spring to feed onbuds and the first flush of leaves.

Red oaks thrive in our region, despite this wide variety ofinsect herbivores, several of which can explode into largepopulations. Here’s one reason: Oaks have tough, stringyleaves that are rich in phenolic compounds, especially tan-

Oak skeletonizer (Bacculatrix ainsliella)

Acorn weevil (Curculio sp.)


nins—a potent chemical used in tanning leather. Tanninsare hard to digest, so that even insects that can consumethem will have stunted growth and reduced egg-layingcapacity. The winter moth, for example, must time its egghatching perfectly. In years when the trees are slow to leafout, the young larvae may starve. In years when themoth’s eggs hatch only a couple of weeks after bud break,the expanding leaves have already developed enough tan-nin to protect the tree. Even when the timing is just rightfor a major defoliation, caterpillar populations may be heldin check by returning migratory birds or by predatoryinsects. Each herbivore of red oak is similarly limited by acombination of plant defenses, natural predators, and envi-ronmental conditions. When major defoliation does occur,the oak can use reserves from its roots to produce a newflush of leaves. The “replacement” leaves of oaks defoliatedby gypsy moths (Lymantria dispar) have been shown to bemuch higher in tannins and fibers; the oak’s response tothe first attack is to partially immunize itself against furthermajor attacks!

Chemical WarfareSome compounds that serve as chemical defenses arealways present in plant tissues, while others are mobilized,or “induced,” when damage occurs. Besides the phenolics,other plant chemicals serve as toxins, and only small con-centrations may be necessary to deter insect herbivores.These compounds are present in a surprising number ofplant families studied (see table below).

The interactions between the production of these com-pounds and the feeding mechanisms of herbivores arecomplex. For example, black swallowtail butterfly larvae(Papilio polyxenes) commonly feed on plants in the carrotfamily (Apiaceae), some of which contain powerful com-pounds that we use as pungent spices (such as fennel, dill,coriander), while others are extremely toxic even tohumans (like water hemlock). Plants in this family areknown for producing an array of toxic compounds calledfuranocoumarins—the pungent odor we smell when wemow the lawn—and only a few herbivores can detoxifythese poisons, which can weaken the chemical bonds in

cells. Some furanocoumarins are activated by ultravioletlight (including the one that produces the powerful humanskin irritations caused by the introduced Asian plant, gianthogweed, Heracleum mantegazzianum). Ecologists havesuggested that, to overcome such effects, the well-adaptedswallowtail larvae wrap themselves up in leaves and then,out of the sunlight, can munch away. Adult butterfliesretain these larval poisons, giving them additional protec-tion from predators.

The Sugar DefenseMany plant species use sugary nectar to attract and rewardpollinating insects. Perhaps even more amazing is the waysome plants use sugar to attract certain small “knights inshining black armor”—enticing ants to protect the plantsfrom herbivores. When ants are established on a plant, theytend to attack any visiting insect that might compete withthem for the plant’s resources. “Extra-floral” nectaries,located on soft tissue, are like tiny sugar pots secretingnectar to attract pugnacious ant mercenaries. Early springleaves of black cherry (Prunus serotina) have nectar glandsat their margins and at the base of petioles—providingenough incentive for ants to defend the tree against easterntent caterpillars. The common bracken fern (Pteridiumaquilinum) of our dry New England woodlands also pro-duces special nectar glands to lure protective ants. No rela-tionship is perfect because ants also utilize sap-suckingaphids as straws to extract large quantities of sugar fromthe phloem cells of many plant species, a decidedly harmfulinteraction for the plant.

United for Mutual ProtectionIn addition to myrmecophily (ant-plant mutualisms, likethe ones above) plants have well-known beneficial associa-tions with mycorrhizae, the fungi that help plant rootsgather nutrients from the soil. But did you know thatother kinds of fungi grow hidden inside the leaves andstems of many plants? These endophytic fungi are particu-larly common in grasses (the well-known ergot of rye, forexample), but also occur in a broad variety of native plants,including ericaceous shrubs and coniferous trees. While theplant supports the fungus with some of its sugars, it is alsoderiving important benefits from the fungus.

It turns out that these undercover fungi produce “myco-toxins” that deter or harm herbivores attempting to feedon the host plant. Studies indicate that some of them willeven produce toxins on demand, only colonizing vital tis-sues when the plant is injured or stressed by an insectattack. So far, scientists have reported clearly negativeeffects such as reduced feeding, diminished egg-laying,poorer survival, slower weight gain, and lower populationgrowth for a variety of insects, including armyworms,aphids, crickets, cutworms, webworms, and stem weevils.

Got Latex?A number of our native New England plants employ ahighly effective form of defense against herbivores—latex.Milkweeds (Asclepias spp.), euphorbs (Euphorbia spp.),some wild lettuces (Lactuca spp.), dogbanes (Apocynumspp.), and a few other species all have special channels run-

Chemical TypesWoody

% of plant familiesHerbaceous

% of plant familiesPhenolics (includingflavonoids, tannins) 85 38

Quinones 38 69

Saponins 8 46

Alkaloids 23 77

Cyanogenic glycosides 23 38

Coumarin glycosides 23 38

Acetylenes 0 23

Sulfur compounds 0 23

Howe, H. and L. Westley. 1988. Ecological Relationships of Plants and Animals. Oxford University Press, New York, New York.


ning alongside the water- and sugar-carrying vascular cells.These “laticifers” carry a thick milky substance that oozesfrom the plant when injured. This latex is sticky, so insectsthat chew on a leaf will very quickly suffer from gummed-up mouthparts and will no longer be able to feed.A few insects have developed ways to inactivate the latexdefense. For example, the milkweed beetle (Tetraopestetrophthalmus), a leaf-feeding long-horned beetle fre-quently found on common milkweed (Asclepias syriaca),knows better than to feed indiscriminately. Instead, it firstmakes a cut across the mid-vein of the leaf; when latexruns out of this injured area, the insect moves its feedingactivity toward the leaf tip. After carefully wiping itsmouth, the beetle chews on the leaf tissue beyond the cut,and encounters very little latex! A variety of other insects,including monarch butterfly larvae (Danaus plexippus) andqueen butterfly larvae (D. gilippus), have independentlyevolved the practice of cutting the main veins of milkweedleaves for the same purpose.

A World of StrategiesI’ve only touched on a few of the many strategies plantsemploy to defend themselves from insects, and merelyscratched the surface of the intriguing world of insectadaptations. We can observe many fascinating plant-herbi-vore phenomena in our own backyards. Both ecologistsand horticulturists have discovered that some plants can re-allocate resources to unattacked parts, and sometimes re-grow sufficiently to fully compensate for damage to stems,leaves, and even flowers. Certain plants, such as nettles(Urtica spp.), are covered with glandular hairs that deterinsects. Other plants form extremely hard ovary walls andseed coats to protect their fruits and seeds. Some specieseven make fake seeds to fool seed-feeding bugs. And manyof our eastern deciduous forest trees produce irregularcrops of fruits—“masting” events when huge numbers ofseeds are released—overwhelming seed predators andallowing new tree seedlings to elude their enemies and get a start.

Recent research suggests that individual plants, especiallylong-lived ones, can be thought of as “genetic mosaics”when it comes to the chemical defensive strategies.Different sections of the same plant may develop, throughmutations, a diversity of chemical profiles. This variabilitymay be an effective way to prevent insect herbivores fromadapting to any one compound. It’s a strategy I thinksome politicians would be proud to adopt!

Save the Relationships, Along with the PlantsAn important lesson has emerged from the study of plant-herbivore interactions: When it comes to conservation, notonly are the species themselves precious, but also theirintricate interactions with each other, which developed andevolved over generations under changing environmentalconditions. Plant-herbivore interactions are worthy of ourprotection. These coevolving relationships between dis-parate species involve genetics, chemistry, physiology,behavior, and anatomy. They are as important here in NewEngland as in the tropical rain forest, and they can’t becryogenically stored in seed banks or replicated in acloning laboratory. Study of plant-herbivore interactionsmay be responsible for one of the next great medical ornutritional breakthroughs, or the development of morelethal weapons (but let’s hope not). In a real sense, ourNew England fauna and flora—these fascinating animals,and the photosynthetic masterpieces they feed upon—aremade for each other.

Milkweed beetle on common milkweed (Asclepias syriaca)

POTENT INVASIVEAn invasive plant in our region, black swallowwort(Cynanchum louiseae), is a member of the plant family(Apocynaceae) that includes the milkweed. Researchershave noticedunsuspectingfemale monarchbutterflies layingeggs on this vine,but their caterpil-lars cannot surviveeating the leavesas food. Whetherthe larval mortali-ty is caused by aunique propertyof the plant’s latexor another toxicplant substance isnot yet known.The lack of herbi-vores andpathogens foundon this non-nativevine may explain itssuccess in displacingnative vegetation as it advances across North Americaand, recently, into New England. Will Cynanchumlouiseae have an impact on our native milkweeds, andeventually threaten the monarch’s northern range?

Black swallowwort seed pod(Cynanchum louiseae)


AntsWildflower Gardeners

Bloodroot seeds (Sanguinaria canadensis)

by Henry Art, Ph.D.,Williams College

Woodlands in the Northeast come alive with wild-flowers in the spring, and gardeners of all sortsturn their attention to planting seeds. Many of

the earliest wildflowers—the “spring ephemerals”—bloomin that window of opportunity when the soils first warmup, before the tree canopy shades the ground layer. Theseplants tend to produce their seeds by late spring when antsof the region are highly active. Surprisingly, ants engage incrucial gardening activities upon which many of our mosthighly prized wildflowers depend.

To observe this interdependence of wildflowers and antsyou will need to get down and dirty, kneeling or lying onthe ground near a patch of wildflowers, such asDutchman’s breeches, trilliums, spring beauties, or tooth-worts, that have gone to seed. The seeds of these wildflow-ers and many others (see page 13) bear a peculiar, special-ized appendage that is known as an “elaiosome,” a termthat means “oily body.” Elaiosomes take a variety of forms,sometimes looking like small roots emerging from the seed(in bloodroot and spring beauties), or like small masses ofjelly (Dutchman’s breeches, trillium, and trout lily).Whatever their appearance, elaiosomes are all highly nutri-tious and attractive to ants, containing chemical com-pounds that lure the small foragers. They are loosely con-nected to the seed’s hard coat, making them easy to remove.

The sole purpose of the elaiosome is to attract ants toseeds and then to reward them when they carry the seedsaway to a new location. Finding ants to attract is usuallynot all that much of a challenge, as most woodlands haveseveral ant nests per square yard. Ants make nests in leaflitter, hollow twigs and branches, even inside acorns. Antcolonies may move their nests several times during thespring and summer, so you may think you have found a nest only to find it abandoned when you visit a short time later.

Seeds with elaiosomes attract ants of five genera, includingAphaenogaster, which carry them off to their nests. Thetrip is usually a short one of less than three feet, but onestudy published in 1998 found that wild ginger seeds aresometimes transported over 100 feet from the parentplant. The ants then typically chew off the oily body anddispose of the otherwise undamaged seed in an abandonednest gallery or midden (an ant’s version of a refuse pile).

These “planting” sites are like miniature versions of ourmanured, mulched, and rototilled gardens. Ants mix bitsof leaf litter and organic debris with their own droppingsand nutrient-rich soil they excavate as they create their nestgalleries. In doing so, they coincidentally create rich seedbeds ideal for the germination of wildflower seeds.Ecologists have found that seeds carried off and planted byants are twice as likely to germinate and survive, whencompared with seeds planted directly where they fall. In

addition to pro-viding the seedswith fertile soilin “safe sites,”away frompredators andcompetingplants, ants alsoscratch the hardseed coats whenremoving theelaiosomes,allowing waterand oxygen tomore readilypermeate theseed and facilitating germination.

Bloodroot flowers, seed capsule, and ant collecting seed


The result of this gardening is that, over time, coevolutionhas taken place between different species of wildflowersfrom diverse plant families and a wide variety of ants. Thewildflowers provide highly nutritious food for the ants andthe ants, in turn, provide a means of moving seeds to newand highly favorable locations. Our studies in western NewEngland have shown the dispersal of wildflowers by ants tobe a very slow process. We found that ant-dispersed wild-flowers expanded their range at rates of between 3 inches(8 cm) per year for hepaticas and spring beauty and 10inches (25 cm) per year for trout lily. At this rate it wouldtake more than a thousand years for these species to spreadthe length of a football field. But ants, like plants, areknown for their persistence.

Dutchman’s breeches seeds (Dicentra cucullaria)

WOODLAND PLANTS WHOSESEEDS ARE DISPERSED BY ANTS

Sedges Carex jamesii—James’ sedgeCarex laxiculmis—Spreading sedgeLuzula echinata—Hedgehog woodrush

WildflowersAnemone quinquefolia—WindflowerCardamine diphylla—Common toothwortClaytonia virginica—Spring beauty Corydalis flavula—Pale corydalis Corydalis sempervirens—Pink corydalisDicentra canadensis—Squirrel cornDicentra cucullaria—Dutchman’s breechesErythronium americanum—Trout lilyHepatica acutiloba—Sharp-lobed hepaticaHepatica americana—Round-lobed hepaticaSanguinaria canadensis—BloodrootTrillium erectum—Red trilliumTrillium grandiflorum—White trilliumUvularia perfoliata—Perfoliate bellwortUvularia sessilifolia—Sessile-leaved bellwortViola blanda—Sweet white violetViola pedata—Birdfoot violetViola rostrata—Longspur violetViola triloba—Early blue violetViola papilionacea—Common blue violet

Henry Art is Director of theCenter for Environmental Studiesat Williams College and overseesresearch at the Hopkins MemorialForest,Williamstown,Massachusetts. His researchincludes successional patterns, landuse history, impacts of acid deposi-tion on soil systems, and nutrientcirculation relationships.

Some of his published worksinclude Woods Walk (StoreyPublishing, 2003), WildflowerGardener’s Guide–various editions–(Garden Way Publishing,1987–1991), and A Garden of Wildflowers (StoreyCommunications, 1986).

Red trillium seeds (Trillium erectum)


Insects Raise Some

GallingQuestionsby Warren G.Abrahamson, Ph.D., Bucknell University

Imagine living inside a succulent, green chamber whoseedible walls provide both food and shelter. Such shel-ters are home to the myriad of insects who manipulate

their host plants to produce abnormal growths called galls.Galls are produced by the host plant in response to thesecretions and feeding of the larvae of these insects, whichare known as “gall-inducers.” Galls are so distinctive thatwe can guess the identity of the insect that stimulated itsproduction simply by looking at the outside of the gall.

Of the more than 1,700 species of gall insects known inNorth America, the majority induces galls on plants in onlythree families—the oak/beech family, sunflower/goldenrodfamily, and rose family. This proliferation of insect speciesattacking so few host-plant families suggests that majorobstacles exist to becoming a gall inducer, but also thatonce a related group of plants is exploited, there are manyopportunities for diversification. Two insect families thathave developed exceptional numbers of gall-inducingspecies are the gall midges and gall wasps. More than 600species of cynipid wasps are known to attack NorthAmerican oaks and we are still discovering new species ofthese wasps. My Hungarian colleague George Melika and Idiscovered 28 species of gall wasps previously unknown toscience during a yearlong survey of Florida oak galls.

The conspicuous spherical stem swellings on tall goldenrod(Solidago altissima) are especially well known to those ofus who stroll through old fields in the Northeast duringlate summer, autumn, or winter. These galls develop inJune and early July in response to the presence of a gold-enrod gall fly (Eurosta solidaginis) larva. Weeks earlier, inlate May, a female gall fly injected an egg into the terminalbud of the rapidly growing goldenrod. Not all goldenrodsare suitable hosts, and if the gall fly chooses poorly, heroffspring may perish due to host-plant defense. Even if thehost plant is suitable, a gang of parasitic wasps, predatorybeetles, and insectivorous birds may kill the gall fly larva.Larvae in large galls with thick walls are protected fromwasp attack, but are attractive to downy woodpeckers.Small galls are ignored by woodpeckers, but are vulnerableto wasps. Consequently, in years when wasps are abundant,natural selection favors larvae in larger galls; however, lar-vae in smaller galls have the advantage when severe winterweather causes birds to exploit more galls for food. Whenthe enemies are balanced, natural selection favors interme-diate-sized galls.


In spite of the presence of over 100 species of goldenrodsin North America, the gall fly selectively attacks tall gold-enrod—with an interesting exception. Across southernCanada and northern portions of New England, NewYork, and Michigan, as well as most of Wisconsin andMinnesota, goldenrod ball galls also occur on late golden-rod (Solidago gigantea). Late goldenrod, however, is notattacked elsewhere across its widespread range. My col-leagues and I have shown, through ecological, genetic, andbehavioral studies, that the gall fly populations that attacktall goldenrod and late goldenrod are distinct host races.

Host races occur with-in a species andbecome isolated fromone another because oftheir association withdifferent host plants.Many researchers con-tend that host races areincipient species.

Male and female gallflies strongly prefer tomate within their ownhost race even thoughthey can mate with fliesof the opposite hostrace. Females show a strong preference for injecting theireggs into the same species of goldenrod as that from whichthey emerged. Furthermore, gall flies associated with lategoldenrods emerge nearly two weeks earlier than tall gold-enrod gall flies, reducing the chance of the two host racesmeeting. These behavioral and ecological differences arelikely responsible for the marked genetic differences thatwe’ve documented between the two host races. While thegenetic differentiation of the host races is less than whatwe might expect between species, given sufficient time, itis very possible that these host races will become separateand distinct species.

Oak acorn galls on myrtle oak caused by the cynipid wasp (Adleriaweldi). Young, green galls secrete honeydew, but at maturity gallsturn brown and drop from their host.

Cross section of a bud gall on blue-jack oak caused by the cynipid wasp(Amphibolips quercuscitriformis). Thelarval wasp grows within a smallcentral chamber that is supported atthe center of the gall by fibers thatradiate to the gall’s outer walls.

Female goldenrodgall fly on tall gold-enrod.

Cross section of anoverwintering goldenrodball gall showing the cen-tral chamber and exittunnel (units are cm).

The parasitoid wasp (Eurytoma gigan-tea) injecting an egg through the wallof a goldenrod ball gall on tall gold-enrod.The wasp’s ovipositor, whichis used to inject eggs, extends fromthe wasp’s body to the gall.

Warren Abrahamson is theDavid Burpee Professor of PlantGenetics at Bucknell University inLewisburg, Pennsylvania. Abrahamsonand his colleagues have extensivelystudied the interactions of golden-rods, gall flies, and the natural ene-mies of gall flies for over 30 years.He also studies cynipid wasps andtheir oak hosts, plant populationbiology and community ecology, andfire ecology at Florida’s ArchboldBiological Station, where he is aResearch Associate.

wasp’s ovipositor

Mature, late sum-mer gall of the lategoldenrod hostrace of the golden-rod ball gall fly

Mature, autumn gallof the tall golden-rod host race ofthe goldenrod ballgall fly


If gardeners generally view bugs as enemies that harassprecious plants (and hopefully this magazine willchange that outlook), then they can take comfort:

Carnivorous plants will have their “revenge.” Carnivorousplants turn the standard notion of the food web upside-down—the plants eat the animals! Children are captivatedby these weird characters out of The Little Shop of Horrors,taking delight in feeding the plants a steady diet of haplessbugs. Scientists (who never really lose touch with theircuriosity-driven “inner child”) can spend the better part oftheir lifetimes studying the intricate worlds contained inthese plants. Three biologists, Aaron Ellison (HarvardForest), Nick Gotelli (University of Vermont), and LeszekBledzki (Mt. Holyoke College)* have been poring overpitcher plants for more than five years now. This article isbased on their research, which has some pretty interestingecological tales to tell.

A Quiet and Carnivorous WorldCharles Darwin provided the first definitive evidence thatplants could consume insects; before his experiments withsundews, people had trouble believing the preposterousnotion of “killer plants.” One hundred years after Darwin,more than 500 species of carnivorous plants have beendocumented from around the world. Some, like sundews(Drosera spp.) and Byblis species of Australia, trap insectson the sticky, glandular hairs that cover their leaves andstems, slowly digesting their pinioned prey. Others, likeVenus fly traps (Dionaea spp.) have folded leaves that aretriggered to snap shut like a cage when an insect lands.The Nepenthes species of southeast Asia are climbing vineswith tendrils that swell out to form graceful, hangingpitchers. Insects hone in on nectar secreted at the lip of thepitcher, then tumble in, drowning in water at the bottom.The aquatic bladderworts (Utricularia spp.) of NewEngland waterways also catch passing planktonic animals inclever vacuum traps arrayed along their floating stems.

KillerPlants of New England and Beyond

by Elizabeth Farnsworth, Ph.D.,NEWFS Senior Research Ecologist

Venus fly trap (Dionaea sp.) captures monarch butterfly (Danaus plexippus)


Tiny EcosystemsThe bogs of New England arehome to Sarracenia purpurea:squat, reddish-green pitcherplants that strike fear in thehearts of wetland insects, par-ticularly ants. A single rosetteof pitchers may live more thanfifty years, and each pitcherharbors a diverse and special-ized menagerie of invertebratesthat digest the prey, releasingnutrients to the host plant.Prey insects that trip into thepitchers and drown are firstchewed and shredded by slimemites (Sarraceniopus gibsoni)and midge larvae (Metrio-cnemus knabi). The crumbsthat remain are colonized bydecomposer bacteria, which areeaten in turn by rotifers(Habrotrocha rosa) and mos-quito larvae (Wyeomyiasmithii), which themselves areeaten by the top predator inthe system, the solitary andcannibalistic larvae of the flesh-fly, Fletcherimyia fletcheri

(something you definitely don’t want to meet in a darkalley). Many of these species are found only inside pitcherplants. Ellison, Gotelli, and Bledzki have identified rotifersas the workhorses of the bunch, suppling most of thenutrients to the plants. Novel families of rotifers—somepreviously unknown on this continent—have been discov-ered inside pitcher plants in Massachusetts and Vermont.

Ongoing studies are finding out what pollinates pitcherplants, discovering the roles of predatory spiders that buildwebs across the pitchers (constructing clever traps upontraps), and elucidating the curious life history of the veryrare root-boring larva of the moth Papaipema appassionata.Pitcher plants may be the terror of the bog for someinsects, but they also provide critical microhabitats for manyspecialized creatures we are only beginning to discover.

Too Much of a Good ThingAll carnivorous plants inhabit nutrient-poor habitats—damp sand barrens, peatlands, granite and sandstone mas-sifs—in which the best source of food comes not from thesoil but from prey. More and more nutrients (particularlynitrogen) are literally falling from the sky in the form ofacid precipitation and the nitrous oxides spewed from carexhaust pipes. Pitcher plants are highly sensitive to thesenew sources of nutrients and, because they now requirefewer inputs from prey, they may produce fewer pitchersand more flat leaves. According to Ellison, Gotelli, andBledzki, pitcher plants are thus excellent indicators of theamount of nitrogen pollution affecting bogs in NorthAmerica. Unfortunately, pitcher plants do not benefit inthe long-term from the extra nitrogen. The populations in

areas with the highest levels of pollution face a higher riskof extinction than those of more pristine bogs, accordingto models developed by the ecologists. If this pollutioncontinues, these “canaries in the coal mine” could ulti-mately disappear, taking their tiny ecosystems of dependentinvertebrates with them.

* Aaron Ellison is Senior Research Fellow at the Harvard Forest in Petersham,Massachusetts. Nicholas Gotelli is Professor of Biology at the University ofVermont in Burlington,Vermont. Leszek Bledzki is Research Associate at MountHolyoke College in South Hadley, Massachusetts. All three have been studying thefascinating world of pitcher plants and bogs since 1996.

Round-leaved sundew (Drosera rotundifolia)

Common bladderwort (Utricularia vulgaris)

Fleshfly (Fletcherimyia fletcheri)

Pitcher plant (Sarracenia purpurea)

Thread-leaved sundew (Drosera fili-formus) with a pearly crescentspot


For anyone who loves plants, the insect world arousesconflicting emotions. On one hand, we know thatplants rely heavily on the intercession of pollinating

and seed-carrying moths, bees, ants, flies, and beetles forreproduction and seed dispersal. On the other hand, it isdifficult to repress pangs of atavistic loathing when insectseat their way through a population of rare species or suckthe life from a beloved specimen plant. And yet, ourstaunchest allies in confronting the army worms, root weevils, and fungus bearers are not petrochemicals, butother insects.

When we think of “beneficial insects,” it is usually thelarge, eye-catching predators that come to mind. The pray-ing mantis (actually several species of mantids), for exam-ple, is cryptically colored and stands motionless—oftennear a prey-attracting blossom—with its grasping forelegsraised, not in prayer of course, but in preparation for thedeadly pounce. The spectacularly iridescent ground beetlescalled “caterpillar hunters” (Calosoma spp.), by contrast,actively pursue their preferred food right into the treetopsif necessary. These carnivores often take pollinators as wellas leaf-munchers but are generally thought to do (us) moregood than harm.

DINING “IN”As insect relationships go, the predator/prey scenario ispedestrian stuff compared to the bug-eat-bug strategies ofthe so-called parasitoid flies and wasps. Most gardenershave encountered the handsome green sphinx moth larva,known as the tomato hornworm. These caterpillars will fre-quently be seen bearing dozens of small, white, egg-likeobjects on their backs. These are the silken cocoons spunby the larvae of a tiny braconid wasp that lays its eggsinside the half-grown hornworm by means of its syringe-like ovipositor. When the wasp larvae hatch, they feed onthe internal tissue of the caterpillar, leaving it weakenedbut alive until the parasites can burrow through their

The Enemyof MyEnemy …by Christopher W. Leahy, MassachusettsAudubon Society and NEWFS Trustee

Praying mantis (Mantis religiosa)on goldenrod (Solidago sp.)


host’s skin and attach their cocoons to its back. The horn-worm soon dies and the wasp pupae either hatch intoadults or overwinter in their cocoons in the leaf litter.

Other parasitoid wasps are so tiny as to be nearly invisibleto the naked eye; some develop inside an insect egg lessthan a twentieth of an inch in diameter, or within the bodyof an adult aphid, or share the interior of a small caterpillarwith as many as 3,000 siblings. Many of these wasps are“hyperparasites”—parasites of parasites. One hyperparasitelays thousands of eggs on the surface of a leaf. When amoth larva consumes the leaf and the eggs, its digestiveactivities stimulate hatching. The resulting wasp larvaehave no interest in feeding on the moth caterpillar and willonly survive if the caterpillar that has eaten it has also beenparasitized by another kind of wasp, the larva of which iswasp larva #1’s preferred prey.

This may seem the ultimate in parasitic hyperbole, butentomologists have confirmed parasites that parasitize parasites of parasites of parasites!

ONLY INSECTS?In the last century well-meaning proponents of biologicalcontrol sometimes promoted the importation of parasitoidsas benign alternatives to pesticides for combating exoticinsect pests. Unfortunately, the parasitoids, like the pests

they were meant to conquer, didn’t necessarily perform asexpected in their new environment. While there have beena few notable successes, there have been many more fail-ures and a few ecological disasters. The tachinid fly(Compsilura concinnata) is one of many alien parasitoidsthat was imported in an attempt to control the gypsymoth. As has been the case with most such imports,Compsilura’s effect on gypsy moths was small, but its tastein hosts proved to be very broad and it promptly began toattack our native butterflies and moths. To date, it hasbeen recorded from over 200 native species in 19 familiesof Lepidoptera and may be implicated in the decline ofsome rare species. Unfortunately, importers of biocontrolagents are not required to test the effects of parasitoids onnon-target species and the prevailing attitude in pest con-trol circles is that biocontrol agents are “safe, because theyattack only insects.”

Only insects? Insect species make up more than 50% of the earth’s biodiversity. They are crucial to the survival of the global flora, without which, life as we know it could not exist.

Christopher Leahy holdsthe Gerard A. Bertrand Chairof Natural History and FieldOrnithology at theMassachusetts Audubon Society.He has been a professionalconservationist for more thanthirty years, most recently asthe Director of MassachusettsAudubon’s Center forBiological Conservation.

His published works includeThe Birdwatcher’s Companion(Princeton University Press,2004), The First Guide to Insects(Houghton Mifflin, 1987),Introduction to New England Birds (Massachusetts Audubon, 1990), AnIntroduction to Massachusetts Insects (Massachusetts Audubon, 1983),and The Nature of Massachusetts (Addison-Wesley, 1996).

Parasite pupal cases on tomato hornworm (Manduca quinquemaculata)

Insect species make up more than 50%of the earth’s biodiversity.

Gypsy moth caterpillars(Lymantria dispar)

Tachinid fly(Compsilura concinnata)


The sustainability of our terrestrial ecosystems isclosely linked to a productive and healthy soil sys-tem. The soil is a complex place that supports a

community of diverse and abundant life forms, includingmany species of plants and life stages. Plants form a com-plex system of leaves, stems, flowers, pollen, seeds, roots,and root exudates that indirectly or directly interact withthe non-decomposed (dead) litter layer, partially decom-posed organic layer, decomposed organic matter layer(humus), and mineral soil.

In addition to plant life, soil also supports a huge diversityof beneficial and pest organisms, including fungi, bacteria,protozoa, nematodes, annelid worms (earthworms andpotworms), mollusks (snails and slugs), vertebrates, andarthropods. The arthropods include isopods (pillbugs),arachnids (spiders, mites, daddy longlegs, etc.), symphy-lans, diplopods (millipedes), chilopods (centipedes),insects, and Collembola (springtails). I mention theCollembola as not being true insects because they are nowconsidered a separate but closely related group.

When it comes to diversity and abundance, the soil-dwelling arthropods are a force to be reckoned with. Theirsmall size and numerically significant populations allowthem to exploit leaf litter and tiny openings and channelsin the soil, and thereby contribute significantly to mostecological plant and soil processes. Many soil arthropods,particularly mites and Collembola, help break down organ-ic matter contributing to nutrient recycling and plant fer-tility. Soil-dwelling mites and Collembola largely go unno-ticed due to their very small size (0.2–2.0 mm); yet theyreach very high densities in organic soils of gardens, lawns,meadows, fields, and woodlands when temperature andmoisture regimes are optimum during the growing season.

Because of their huge numbers and diverse feeding habits,soil arthropods are also useful as biomonitoring tools forresearchers who measure the effects of certain land man-agement practices. Prescribed burning used in the mainte-nance of grasslands, clear cutting in forests, and pesticidesapplied to high-maintenance home and commercial lawnsare a few examples of land management practices that areresponsible for a sharp decline in soil mite and Collembolapopulations as well as other groups of soil life. Theirdecline means a temporary interruption in the naturalprocess of organic matter decomposition that contributesto a balanced and fertile soil. Of all of the soil arthropods,it is the soil mites and Collembola that share prime respon-sibility for making whatwe consider an organicsoil organic. This islargely because they aremembers of an ecologi-cally important groupcommonly referred to as decomposers.

In general, decomposerarthropods—togetherwith soil fungi and bac-teria—work in concertat reducing organicmatter to a usable nutri-ent form for plants orfor microbial use. Forexample, when a leaffalls to the ground, it isfirst attacked by slugs,snails, earthworms, pot-worms, millipedes, and

Life DowDirty Littl

Centipede

Slugs


certain insects that chewup the leaf. Soil fungiand bacteria soften orcondition the leaf andthen colonize these bit-ten holes and leaf pieces.Further feeding occursby soil mites andCollembola. As morefeeding takes place bythese and other inverte-brates, the leaf is furtherbroken down by morefungi and bacteria aswell as the bacteriawithin the intestinaltracts of these feedinginvertebrates, eventuallyprocessing the fallen leafinto an unrecognizableform. This complex

decomposition process turns the leaf from a component ofthe litter layer into a complex of readily available nutrientsfor plant root uptake. Our gardens, lawns and natural areascontain plant litter, decaying vegetation, animal remains,and dung—all subject to the action of the vast array of soilorganisms that are essential for nutrient recycling and plantfertility. Without these organisms reducing organic residuesto a usable form, plant life would have limited growthpotential and most species would shortly disappear.

These remarkable microarthropods are all around us. Mostare no bigger than a pencil dot. When you take just tensteps across an organically maintained lawn, your feet haveliterally covered and touched close to 10,000 microarthro-

pods (mostly soil mites and Collembola) that are living inthe uppermost four inches of soil. It may take special sam-pling techniques and the use of a microscope to see thesecreatures in detail, but it is well worth the effort when onerealizes the subtle but very powerful ecological roles theseorganisms play in sustaining plant/soil relationships. So,the next time you take a walk through the woods, a wildarea, or even your backyard, may you have a better appre-ciation for all the unseen life forms and their activitybeneath your feet. These soil organisms are contributing inno small way to sustaining the plant life we value and enjoyevery day.

Bruce C.Wenning is Horticulturist, Property and GreenhouseManager at the Massachusetts Audubon Society’s Habitat WildlifeSanctuary. He has worked at Habitat for 13 years and has been thegrounds manager for 10 years. He has a degree in Plant Pathologyand a degree in Entomology from UMass/Amherst, and a master’sdegree in Biology from Harvard University Extension School.

Prior to working at Habitat heworked for Dr. Patricia Vittum,UMass Field Station,Waltham, in turfentomology. One of his majorresponsibilities was identifying allbeneficial arthropods collected fromturfgrass/insecticide trials. He testedthe effect of MOCAP (a turfgrassinsecticide) on the beneficial arthro-pods of fieldgrass for his master’s thesis.

wn Under:e Secrets

Earthworm

Pillbugs

by Bruce C. Wenning, Massachusetts Audubon Society, Habitat Wildlife Sanctuary


Fifty years ago, after decades of heavy reliance onchemical insecticides, growers, researchers, mer-chants, and the general public began to realize that

they might be creating more problems than they weresolving. Pests were developing resistance to these products,while many beneficial insect species appeared to be morevulnerable than were the pest populations they wereintended to control. Resistance not only generated agreater reliance on pesticides for existing pests, but often,due to removal of natural predators, prompted outbreaksof insects that had not been problems in the past.

Then, in the early 1960s, Rachel Carson very eloquentlypointed out where humans had gone wrong in theirunderstanding and approach to managing insect pest prob-lems. Her book, Silent Spring, was the bombshell thataltered the (then) current way of thinking. Through strongresearch and compassion for a healthy world, Carsonopened people’s eyes to the potential effects that they werehaving on the environment, health, and other organisms.Due to her efforts, Carson is often referred to as themother of the environmental movement. Her workreminds us of what we had chosen to forget: For everyaction that we take in nature, nature will react and it maynot be in a manner that works to our liking or benefit.When dealing with nature, there will be fewer unexpectedsurprises if disruption is kept to a minimum, thus giving usthe old adage, “The less that you mess with the system thebetter!” Lastly, Carson reminds us to pay attention to thelarger scope of our actions because we are a part of thevery system that we are disrupting.

Enter Integrated Pest Management (IPM). The conceptsupon which IPM is built are not new. The plant patholo-gist never had the arsenal of chemicals that was possessedby the entomologist and, therefore, always had to employa more holistic approach to the understanding and man-agement of problems. IPM is a return to those standardsof smart plant and pest management. It allows for the judi-cious use of pesticides, but only after a thorough analysisof the situation. There are many definitions of IPM, but allrelate to the use of knowledge, horticulture, protection ofhuman health and the environment, and the encourage-ment and protection of beneficial organisms. To properlyuse IPM, one must have a good working understanding of

horticulture, specific pests, tolerance levels for pest popula-tions, and the least toxic approaches for management. IPMis a toolbox of knowledge that we never finish filling.

IPM programs exist for many commodities, from vegetableand fruit production to such non-food categories as turfand lawn, nursery, landscape, tree care, and greenhouseproduction. IPM is applicable to native plant horticultureand even the care of natural areas. All IPM programs arebuilt upon the following seven steps: 1) Identifying the pest and the plant it attacks2) Monitoring pest numbers and plant damage3) Identifying economic/aesthetic injury thresholds 4) Developing the right treatment 5) Understanding the correct timing for treatments 6) Record-keeping 7) Evaluation

IdentificationEffective IPM practitioners must be able to identify theplants in their care. This includes knowing the biologicalneeds of those plants, such as soil, nutrient, pH, siting, andfertility requirements. This is important, because a plantthat grows under stressful conditions will always be moreprone to insect and disease problems. The practitionermust also be able to identify the inherent pests of thoseplants, and know their life cycles, the injuries they maycause, and the times when they are active. Finally, identifi-cation of the beneficial organisms within a planting is amust if they are going to be encouraged and protected.

MonitoringMonitoring of the pest is the backbone of any IPM pro-gram. Frequency of monitoring depends on the plantsinvolved, the specific pests, weather conditions (such asdrought), and geographic location. Techniques for moni-toring range from simple visual observations (perhapsaided by a hand lens), to shaking a branch or limb over apiece of paper to inspect for tiny pests such as mites, to theuse of various traps that attract insects. Such monitoring tells us if a pest is present and offers some idea as to the numbers present.

Integrated Pest ManagemeThe Intelligent Approach to Pest Problems


Identifying Economic/Aesthetic Injury ThresholdsThe Economic Threshold Levels (ETL) for food com-modities have been established for many years. The simpledefinition of ETL is: When the cost of managing a pestNOW equals the potential loss at harvest time (in dollars),then NOW is the time to treat. Ornamental agriculture(turf, landscape, etc.) presents a different set of choices.The value of these plants lies in their inherent beauty andtheir contributions as wildlife habitat as well as utility forhuman activities. They are chosen for size, shape, color,habit of growth, flowers, as well as other subjective factors.For the most part, there are no “harvest” values. Placing aset threshold for tolerance here is nearly impossible giventhat everyone has a different set of aesthetic values.Professionals who are controlling pests for individualclients must establish a good understanding of their clients’wishes. However, IPM stresses that farmers and homeownerscan usually learn to live with a certain number of pests with-out experiencing unacceptable loss in dollars or aesthetics.

Knowing the Right Treatment and the Correct TimingIn the old days, not so long ago, pesticides were routinelyapplied whether they were needed or not. During the hey-day of chemical pesticide usage, many landowners stoppedlooking for pests and just applied chemicals to their cropsor ornamentals every one to two weeks. Back then, theproducts were inexpensive and seemed to offer a sort of“insurance” that brought peace of mind. That approach iswaning, with the exception of some lawn care programsthat still result in routine over-application of pesticides.Today, working with the principles of IPM, we not onlywait to see if pest populations will build to unacceptablelevels before we intervene, we also need to employ a strate-gy that will remove the pest without harming the rest ofthe system. Such a strategy includes: ● manual removal of pests when it is practical;● horticultural oil sprays that kill mite eggs but not much

else on a particular plant;● Bacillus thuringiensis (B.t.), a bacterium that is specific

to caterpillars that turn into moths and butterflies;● insecticidal soap that targets smaller soft-bodied insects

such as aphids and young caterpillars. Gone are the days when we reached for the chemical pesticide first!

These newer products, often referred to as “bio-rational”pesticides, can be very effective in managing specific pests,but success depends on applying them at the correct timein the life cycle of the pest. B.t. is an excellent product forcertain caterpillar pests, but is only effective against theyounger caterpillars. When applied to older caterpillars, it may not work at all. Of course, any control method should be weighed against its potential effects on non-target organisms.

Record-keeping and EvaluationIn any IPM program, it is essential to keep high qualityrecords of observations and actions taken. Such observa-tions include weather conditions and patterns, sources ofwater for irrigation and pesticide application, soil analysis,timing for applications, and all other associated factors.

Without quality records, it becomes difficult to perform ameaningful evaluation of one’s own work. The practitionerof Integrated Pest Management is always striving to learnmore and good records are crucial to this aim, especially ifany specific action yields less than desirable results.

IPM in the 21st CenturyThrough the seven steps outlined above, it is possible toreduce our reliance on chemical pesticides by a substantialamount and still maintain acceptable economic and aes-thetic results on the farm or in the garden. Increasingexperience and knowledge will bring further successes asIntegrated Pest Management moves into the 21st century.

Robert D. Childs is an instructor ofEntomology at the University of Massachusettswhere he teaches three courses a year, allbased in IPM. His specialty area of entomologyis with those insects that attack trees andshrubs. In addition to teaching, he is anExtension Specialist serving the Green Industry(non-food agriculture) in Massachusetts byoffering pest identification, recommendationsfor management, and publications.

This article is dedicated to Dr. Ronald Prokopy (University of MassachusettsEntomology Department), one of the pioneers of Integrated Pest Management.He will be remembered worldwide for his research in IPM and tree fruit insects.

ent (IPM):by Robert D. Childs, University of Massachusetts


After reading the articles in this issue of NewEngland Wild Flower, I hope you’re ready to createan inviting haven for these amazing creatures (now

knowing they won’t all devour your plants). Creatinginsect habitats is one of the many satisfactions of practicingecological landscaping, so let’s start there.

An ecological landscaping ethic assumes that people arestewards of the land. Cultivated spaces are a partnershipwith nature; landscaping is done with an eye toward conserving resources and limiting adverse effects on thesurrounding environment. Five basic principles govern this approach.

LIMIT THE USE OF PESTICIDESThese chemicals were developed to destroy target insects,plants, and diseases. Even if an insect is not the intendedtarget, it can be affected by use of these products. Forexample, a bee might accidentally consume residual pesti-cides while collecting pollen. Biological controls such asthe bacterial Baccillus thuringiensis (B.t.) can affect morethan one Lepidopteran species, not just the targeted gypsymoth or tomato hornworm. Caterpillars feeding onsprayed plant leaves in spring may translate to fewer butter-flies sipping flower nectar in summer. So, as the IPM arti-cle indicated, understanding the plant, the pest, and thesituation are all important. Using B.t. on cabbage loopersin your vegetable garden will probably only affect thatspecies. But spraying B.t. on an oak to control gypsy mothswill affect other moth and butterfly caterpillars on that tree.

For gardeners striving to grow the perfect plant, try thesesuggestions to shift the paradigm in favor of insects beforeyou reach for a “treatment.”

1. Tolerate imperfection. Most insects do not consume aplant completely. Let go of total ownership of the plant,and remember how you learned to share in kinder-garten. Insects provide crucial nutrients for many song-birds, so think of it as sharing your plants with birds aswell as insects.

2. Wait and see. If you are patient and your gardendiverse, natural predators may bring balance. Encouragepredators by growing certain plants. For example, membersof the Apiaceae family, such as parsley, golden Alexanders,and Queen Anne’s lace, boost populations of parasiticwasps which prey on undesirable insects such as aphids,weevils, and leaf miners.

Ecological LaAn Open Invitatioby Cheryl Lowe, NEWFS Horticulture and Botanical Garden

Bee on Virginia bluebells (Mertensia virginica)


ndscaping:n to Insects

n Director

3. Physically remove insect pests you can’t tolerate byspraying them with water or picking them off. (This ishow we control lily leaf beetle at Garden in the Woodsmost years.) Incidentally, if the pest is a weed ratherthan a bug, try repeated pulling or cutting before reach-ing for an herbicide.

4. Use the least toxic pesticide available first, such assoap spray, and treat only the problem plants. Don’tspray “just in case.”

5. Consider removing the plant if insects and diseasecontinue to be a problem. I know this is difficult advicefor many gardeners, especially if the plant has capturedyour affections, but think of it as an opportunity toplant something new, different, and easier to manage.

BUILD HEALTHY SOILS Healthy soils support a wealth of organisms from fungi andbacteria to springtails, beetles and earthworms (and, ofcourse, plant roots). (See “Life Down Under” on page20.) In fact, I think soils teeming with life are the anchorfor a healthy ecosystem. Adding organic matter such ascompost, aged wood chips, or leaf mold is the easiest routeto healthy soils. Organic matter soaks up moisture like agiant sponge, slowly releasing it to plant roots.Furthermore, its physical structure, extending the spongemetaphor, creates air spaces essential for roots to breathe.Organic matter also binds nutrients, including fertilizers,holding them for plant roots, as well as releasing nutrientsas the organic materials decompose (thanks to fungi, bacte-ria and those bountiful bugs).

RIGHT PLANT IN THE RIGHT PLACENew Englanders are blessed with an incredibly diverselandscape. Choose plants that grow well in your site’s con-ditions—plants adapted to those conditions will look bet-ter, stay healthy, and resist disease or insect pests withmuch less help from you.

MINIMIZE USE OF FERTILIZERSIn nature, plants grow without supplemental fertilizers. Ingardens, they are close together, forced to compete forlimited resources, so a little fertilizer does help plants growbetter. Too much fertilizer, or the wrong kind, can damageplants or be washed into streams, rivers, and water sup-plies. Organic or slow-release fertilizers (especially in com-bination with organic matter to bind the nutrients) arebest for avoiding these problems.

CONSERVE WATER Provide water only when it is needed. Monitoring rainfalland soil moisture before turning on sprinklers conserveslimited water resources and helps control certain diseases.Use soaker hoses and drip irrigation to conserve even morewater. In addition, use of mulches will prevent evaporationof soil moisture and control weeds. Convert some of yourlawn to mixed borders or shrub beds, which absorb morerainfall, keeping water on site rather than sending it to thestorm water basins.

We create cultivated landscapes because we want to sur-round ourselves with beauty, with sights, sounds, andsmells that give us pleasure. Ecological landscaping addsthe music and dance of insect wings. Your backyard can bea haven for a wild insect party, hidden in soil and bark, orvisible on flowers and vines. Invite them in.

Eastern tailed blue (Everes comyntas)

Sweet Temptationby Lisa Mattei, NEWFS Publications Manager

During the evening hours, you can continue to search for insectsin your landscape with an activity for all ages, called “sugaring.”Many moths as well as butterflies feed on tree sap or fruit.Youcan attract more elusive moths of the night by painting treesalong forest edges with a sweet mixture they adore.

The sugary recipe is made in various ways, with brown sugar asthe main ingredient. Use a half pound of brown sugar, one over-ripe banana (mashed), and two ounces of apple cider vinegar.Youcan replace the vinegar with stale beer, fruit juice, or molasses.Try adding vanilla extract or a sweet liqueur to see if the mothshave a preference. Good bait should be both smelly and sweet-tasting, and for best results it should also be allowed to fermentfor a day or two.The mixture should be thick enough so it willnot run off the tree.

On a hot, humid night, just before dusk, use an old paintbrush tospread the mixture—at eye level in one-foot squares—on thetrunks of trees.Wait an hour or two, then use a flashlight, withthe lens covered by red cellophane or red paper, to check outthe visitors. Other insects, such as beetles, earwigs, and ants, willalso gather at the sugar. During the day, butterflies too areattracted to the sugared trees.

Tiny Destroyer oTiny Destroyer o

One of the most destructive plant pests to affecteastern North America in recent times is the hem-lock woolly adelgid (Adelges tsugae), a small insect

similar to an aphid, that is infecting and destroying nativeand ornamental stands of the eastern and Carolina hem-lock (Tsuga canadensis, T. caroliniana) from Virginia toNew England.

Hemlock woolly adelgids and aphids belong to the sameinsect order, Homoptera, which is characterized by theinsect’s piercing and sucking mouthparts. Mature hemlockwoolly adelgids are about the size of a pinhead, and theiregg masses look like small white bits of cotton lodged onthe underside of a hemlock branchlet at the base of theneedles. They produce two generations per year, one inspring, the other in autumn. In New England, the eggslaid in March or April hatch in April and May and theinsects begin life in a mobile, or “crawler,” stage for a fewdays until they permanently attach themselves to the baseof the needles and begin feeding as nymphs. At the crawlerstage, the pest is the most vulnerable to control treat-ments. They are difficult to see with the naked eye, butwith a 10x hand lens they appear as tiny black spots thesize of sesame seeds with a white fringe along the edges.As stationary nymphs, they develop a waxy, protective coatand mature to produce new egg masses by the end of June.This second generation develops into crawlers and nymphs,but enters into a dormant state until October when theinsects resume feeding.

Understanding this life cycle helps with the timing ofIntegrated Pest Management strategies to control theinsect. Wind, birds, or forest animals move adelgids fromone tree to another. Human activities, such as transplanti-ng trees or driving through infested areas, can also serve asvectors. For minor infestations on small trees, sprayingwith water using a straight-stream hose tip will help dis-lodge eggs and crawlers, but for more severe infestations,consider professional treatments synchronized to when thecrawlers are present. Two kinds of treatments are normallyused: drenching with a fine horticultural oil spray, whichsmothers the insect, or a systemic application, which uses a

toxic insecticide that is taken up internally, but does notharm the tree; the adelgids are then poisoned as they feedon the tree. Cultural practices, such as maintaining a con-sistent watering regime (especially during periods ofdrought), and pruning back dead wood are also helpful inslowing an adelgid infestation. Infected dead wood shouldbe disposed of so it does not re-infect, and hand tools

Stands of dead hemlock trees


of Mighty Forestsof Mighty Forests by Pam Thomas, NEWFS Horticulturist

Woolly adelgid on hemlock branches

should be properly sterilized by spraying with rubbingalcohol or a bleach solution. Interestingly, studies haveshown that application of nitrogen fertilizer, which stimu-lates tender new growth, increases the rate of infestation.

We’re glad to report that our hemlock collection atGarden in the Woods contains a high percentage of healthytrees, and we have not yet suffered any major damage fromhemlock woolly adelgid. We check 150 individual speci-mens within the garden once a year by inspecting thelower branches. The inventory conducted in autumn 2003 revealed that 10 percent of our hemlocks had a slight infection of adelgid. We have been treating minorinfestations with horticultural oil sprays in spring andautumn since 1999. We chose horticultural oil sprays overa systemic insecticide because the latter eliminates all insectactivity (including the beneficial effects of predaceousinsects) on that tree throughout the year. Recent researchshows the potential for outbreaks of harmful spider mitepopulations following systemic applications.

A cold winter and rainy spring in 2004 created optimalenvironmental conditions for discouraging adelgid activity,and in the northern limits of the hemlock’s range, severewinters are expected to continue to hold back expansion ofthe insect’s infestation area. There are predictions thathemlock woolly adelgid may be as devastating to our east-ern forests as last century’s chestnut blight, which changedthe face of our nation’s forests forever. The damage hem-lock woolly adelgid has already caused in the southeastregion of the country and in southern New England justi-fies preemptive action. The dynamics of the adelgid’s cold-tolerant adaptability, the hemlock’s resilience in retreatingto the northern limits of its range, land uses, climate, andinnovative control strategies will all play a part in the east-ern hemlock’s long-term survival in our forests. For culti-vated trees, a combination of favorable environmental conditions, healthy cultural practices, monitoring, andselective spraying will help stave off the effects of this trulychallenging pest.

Taking the Long View on Hemlock Declineby Elizabeth Farnsworth, Ph.D., NEWFS Senior Research Ecologist

Faced with an imminent decline of a beautiful coniferthat dominates so much of the New England landscape,it’s easy to become discouraged and to mourn thewholesale loss of trees. It’s important to step back andrealize that this resilient species has been with us a verylong time and will likely persist for millennia beyond thissignificant setback. Hemlock rapidly expanded thenortheastern edge of its range more than 10,000 yearsago, closely following the northward-retreating fronts ofthe massive glaciers that once covered the region. Cold-hardy, tolerant of shallow, rocky soils, and producingdeep shade that excludes many other trees, hemlocksquickly gained supremacy over large stretches of newlyavailable New England real estate.

Then, around 5,000 years ago, hemlocks strangely andsuddenly decreased. Records from pollen cores takenthroughout the Northeast show a dramatic drop in theamount of hemlock pollen during this time. Hemlockwas the only species affected, which leads many ecolo-gists to the conclusion that an outbreak of a ratherselective insect herbivore (whose identity remains a mys-tery) was responsible for decimating the tree popula-tions. This had sweeping effects on forest structure inthe region: Analyses of pollen profiles reveal that birch(Betula spp.), beech (Fagus grandifolia), sugar maple(Acer saccharum), and certain oak (Quercus) speciesenjoyed a window of opportunity and proliferated inforests at the time. Hemlock took about 2,000 years torecover from its nosedive and to approach its formerabundance, but by a few centuries ago, it was back in allits grandeur. Nature is exuberant and tenacious; if only afew versatile hemlocks survive the onslaught of the woollyadelgid that may be enough to ensure the survival of thespecies. We might mourn hemlock’s temporary decline,but our grandchildren’s grandchildren may celebrateits return.



Let’s take an imaginary field trip across the wilds ofNew England in search of rare insects! First, we’llchoose a sunny spring day to visit the pine barrens,

a place where the sandy glacial outwash soils foster plantsadapted to dry conditions and scarce nutrients. We’ll go toa place where not too many years ago a wildfire sweptthrough, consuming the dead, dry vegetation and clearingthe way for forbs and grasses to grow beneath the pitchpines (Pinus rigida) and amidst the thickets of scrub oak(Quercus ilicifolia), huckleberry (Gaylussacia baccata), andlowbush blueberries (Vaccinium spp.). Here we find patch-es of wild lupine (Lupinus perennis), with its showy purpleflowers, and wild indigo (Baptisia tinctoria), the twolegumes upon which the caterpillars of three rare butterflies feed.

We are rewarded almost immediately with the dancingflight of a frosted elfin (Callophrys irus), alighting on theflowers of a lowbush blueberry. Another frosted elfin fliesby, and the first takes to the wing in hot pursuit. The twodisappear in a spiraling flight, up over the pine trees. Nowlet’s follow the sandy road to the top of a nearby hill.There—on a moist patch of clay in the road—sits one ofNew England’s rarest butterflies, the Persius duskywing(Erynnis persius persius). The Persius probes the clay withits proboscis, imbibing fluids and salts. We must moveslowly, for it is a flighty fellow—oops, there he goes, dart-ing away into the underbrush. Farewell, little Persius. With

any luck you willfind a mate andyour progeny willspend the warmdays of early sum-mer in this place,feeding alongsidethe frosted elfincaterpillars on the wild indigoand lupine.

Frosted elfin (Callophrys irus) on lowbush blueberry

The majorthreats to rare insectsare habitat destruction

and degradation.

A Daydream JourneySearching for Rare Insects in New England

by Mike Nelson, Massachusetts Division of Fisheries and Wildlife

Persius duskywing (Erynnis persius persius)

Once these barrens were home to a third lupine butterfly,on the federal endangered species list, Karner blue(Lycaeides melissa samuelis). We shall not see the Karnerblue today, as it is long gone from these parts. Habitat lossand fire suppression have extirpated it from New England,with the exception of a small population near Concord,New Hampshire, maintained by importing butterflies fromthe Albany Pine Bush in New York. Contemplating thefate of the Karner blue, and hoping the Persius duskywingisn’t soon to follow, we head down the sandy path on theother side of the hill.

Stop! Look there—the sinuous, low flight of a tiger beetle.Could it be? Yes, a barrens tiger beetle (Cicindela patru-ela). Approach slowly, for this fearsome predator of smaller

creatures is quitewary of us.Suddenly, with aflash of movement,the barrens tigerseizes a nearby ant.The ant strugglesfeebly, but isquickly dispatchedby the tiger beetle,who consumes itwith relish. Aminute later theant is no more

than fragments. The barrens tiger scurries off down theroad, to find more prey for her insatiable appetite. It is agood thing that she is so much smaller than we are! Icould spend the entire day—and many more after that—inthese sunny pine barrens, but we must visit two more des-tinations before spring is through.

BOG BEAUTIESYou may want boots or waders for our next stop, a bog ofsphagnum moss in southern New England. The mossforms a floating mat where carnivorous pitcher plants(Sarracenia purpurea) and sundews (Drosera spp.) grow

between the shrubby patches of leatherleaf (Chamaedaphnecalyculata) and sheep laurel (Kalmia angustifolia). ScatteredAtlantic white cedars (Chamaecyparis thyoides) are inter-spersed with highbush blueberry (Vaccinium corymbosum)shrubs, covered in tiny white blossoms. We hope to findour quarry at the blueberry flowers, but instead it is upona blooming red chokeberry (Aronia arbutifolia) that wespot a nectaring Hessel’s hairstreak (Callophrys hesseli). Itsgreen, white, andbrown wings flash inthe sun, and it istruly a sight tobehold. As quickly asit appeared, it flapsits wings and disap-pears into the tops ofthe cedars, where itfed as a caterpillar.Before we leave, let’scheck the dirt road atthe periphery of thebog, known to be haunted by a rare dragonfly. Sureenough, there are several ringed boghaunters(Williamsonia lintneri) perching on rocks and trunks ofnearby trees. Like the barrens tiger beetle, they are preda-tors, consuming mosquitoes and other small insects to fueltheir darting and gliding flight above the bog.

Barrens tiger beetle (Cicindela patruela)

Hessel's hairstreak (Callophrys hesseli)

Ringed boghaunter (Williamsonia lintneri)



Our last spring destination is another sphagnum bog, thistime in northern New England. In some ways, this bog issimilar to those in southern New England, but with oneimportant difference—black spruce (Picea mariana) treesdominate instead of Atlantic white cedar. Here, flyingabout the sphagnum pools in which they spent the previ-ous season as aquatic nymphs, we find the cousin of theringed boghaunter—the rare ebony boghaunter(Williamsonia fletcheri). Looking past the sphagnum pool,we spot small, dark, elfin-like butterflies darting aroundthe tops of the spruces. Let’s wait near the mud bank atthe base of the trees, for like the Persius duskywing in thebarrens, these butterflies are fond of puddling. Sureenough, before too long, a bog elfin (Callophryslanoraieensis) descendsfrom the top of a spruceand lands on the bankof mud. He doesn’t staylong, soon returning tothe tops of the trees toengage in territorial bat-tles with other males,and to chase passingfemales with hopes ofmating. As withHessel’s hairstreak onAtlantic white cedar,bog elfin caterpillarsfeed on but a singleconifer, in this caseblack spruce.

VALLEY RARITIESOur daydream journey drifts to summer, and over to themarble valleys of southwestern New England. We’ll stop ata place where water flows through lime-rich ground, an

open, sunny wet-land in the fertilevalley. This calcare-ous fen is the onlyhabitat in NewEngland where thedion skipper(Euphyes dion) canbe found. Onceagain donningboots to wadethrough the muck,we wander amongthe sedges thatdion skipper cater-pillars feed upon.The dions arehere, dartingabout with aston-ishing speed andagility. They frequently stop to perch on the sedges, butsoon zoom away again. Finally, a female lands on a nearbyblue flag iris (Iris versicolor), and we get a good look whileshe nectars. Her wings are somewhat worn, as she has beenout and about for a few days. Fully sated, she darts away insearch of sedges on which to lay eggs.

For our final destination, let’s climb the limestone outcropjust west of the fen. The outcrop is wooded with variousoak (Quercus spp.) and hickory (Carya spp.), and an occa-sional hop hornbeam (Ostrya virginiana). The canopy issparse, letting in plenty of sun to nourish a diversity ofunderstory herbs and grasses. One plant in particularcatches our attention, broad-leaved ragwort (Senecio obova-

Ebony boghaunter (Williamsonia fletcheri)

Bog elfin (Callophrys lanoraieensis)

Dion skipper (Euphyes dion)

Northern metalmark (Calephelis borealis)


tus), which is the only food for caterpillars of one of NewEngland’s rarest butterflies. And there is the spectacularinsect itself—the northern metalmark (Calephelisborealis)—nectaring at black-eyed Susan (Rudbeckia sp).Further up the hill, in patches of sun filtering through thegreen leaves of the trees, a dozen or more metalmarks aredancing amidst the flowers.

Let us linger here awhile.

Mike Nelson is Invertebrate Zoologist with the Natural Heritageand Endangered Species Program of the Massachusetts Division ofFisheries and Wildlife. His duties include biodiversity inventory andresearch and conservation planning and mapping. He is also a Ph.D.student in Entomology at the University of Connecticut.

RARE HABITAT = RARE INSECTS

The major threats to rare insects are habitat destruction and degradation. Pine barrens habitats have been dramaticallyreduced from their historic extent by development and the habitat quality of most remaining New England barrens isseriously compromised by fire suppression practices. Wetland habitats such as bogs and fens are also threatened, not onlyby outright destruction, but also by degradation as a result of invasion by exotic plants. Another major threat to rareinsects is introduced exotic parasitoids (wasps and flies) that prey on immature insects.

The table below summarizes the conservation status in each New England state of the ten rare insects discussed in thetext. The terms “Endangered,” “Threatened,” and “Special Concern” refer to official state list status. “Historic” specieshave not been recorded in the state in at least 20 years; an “Extirpated” species is presumed to no longer occur in thestate. “Rare” indicates that a species is present in a state but is not on the official state list. The symbol “—” means thata species is not known to have ever occurred in the state.

Rare Insect Connecticut Maine Massachusetts New Hampshire Rhode Island Vermont

Barrens tiger beetle (Cicindela patruela) Extirpated — Endangered Historic Historic Special Concern

Ebony boghaunter (Williamsonia fletcheri) — Rare Endangered Rare — Rare

Ringed boghaunter (Williamsonia lintneri) Endangered Endangered Endangered Endangered Special Concern —

Bog elfin (Callophrys lanoraieensis) — Rare Threatened Historic — —

Dion skipper (Euphyes dion) Threatened — Threatened — — Rare

Frosted elfin (Callophrys irus) Special Concern Extirpated Special Concern Endangered Special Concern —

Hessel’s hairstreak (Callophrys hesseli) Endangered Endangered Special Concern Historic Special Concern —

Karner blue (Lycaeides melissa samuelis) — Extirpated Extirpated Endangered — —

Northern metalmark (Calephelis borealis) Endangered — — — — —

Persius duskywing (Erynnis persius persius) Endangered Extirpated Endangered Endangered Historic Historic


DAVE WAGNERAgainst Insect Extirpation

Dave Wagner, AssociateProfessor in theUniversity ofConnecticut’sDepartment of Ecologyand EvolutionaryBiology, is grateful formany of the power linesin the New Englandlandscape. “It’s a bit of aparadox that these rights-of-way have turned outto be critical habitats for

so many insects.” The power companies might even bepardoned for their herbicide use, which, while bad for indi-vidual organisms, overall helps maintain early successionalhabitat in our increasingly forested region.

Wagner’s concern for habitat stems from his research inthe field of conservation biology of invertebrates. Withinthe past 50 years, nearly five percent of Connecticut’s resi-dent butterfly fauna has been extirpated. Connecticut’srecently completed Butterfly Atlas project suggests thatnearly a quarter of the state’s 101 resident butterfly speciesare now rare or in decline. In some sense, Wagner lamentsthat we have done too good a job in taming nature’s dis-turbance forces of brush fires and floods, which 100 yearsago, maintained theregion’s sandplains,barrens, and otheropen habitats.

One habitat Wagnerfinds particularlyinteresting is sanddunes, which hedescribes as an“ecosystem of tyran-

ny.” Largely devoidof plants, dunescontain a dispropor-tionate number oflarge-eyed fiercepredators—beewolves, ant lions,and robber flies.Wagner quips that“If humans wereshrunk down toinsect size, we sure-ly would not survivea trip across thesesands.”

Along with histeaching, research,and student men-toring at theUniversity ofConnecticut, Wagner serves on the Connecticut StateDepartment of Environmental Protection, AdvisoryCommittee on Endangered Invertebrate Species. He isclearly an outright and effective advocate for NewEngland’s invertebrates, ant lions and all.

Polyphemus moth (Antheraea polyphemus)

Cecropia larva

Luna moth (Actias luna)

Four insect experts talk aband show their close encounte

Interviews with Insect


JACKIE STONEA Wry Eye on Insects

“Did you know theyhave nose hairs?”

Jackie Stone is awoman fascinated withbugs. She’s the kind ofperson who will buy aplant from a nurseryespecially because it isinfested with caterpil-lars. She takes greatdelight in sharing herphotographs, includinga recent close-up of a

grasshopper that is indeed sprouting nose hairs. A NEWFSTrustee, amateur entomologist, and insect photographer,Jackie coauthored Through the Eyes of a Butterfly, a bookletpublished by the National Council of State Garden Clubsin 2001.

Although she earned an MBA from Boston College andspent twenty years as a businesswoman, Jackie’s heart hasalways been with bugs, creatures that are “too often invisi-ble and ignored.” As a child, her earliest memory is turn-ing over a rock and being amazed at finding sow bugs.With a meticulous housekeeper for a mother, Jackie neversaw a bug in her own house, so was delighted to discover

this world of creepy crawlies outside. Thus began a careerof collecting bugs in a jar, which continues to this day.Katydids, grasshoppers, dragonflies, spiders and such areoften found in Tupperware containers in her refrigerator,since cooled creatures are easier to photograph.

Through her close-up lens, Jackie admits to a sense ofvoyeurism when observing the minute details of insectlives. Her photographs allow an intimacy with these tinycreatures that occupy every possible niche on earth, fromthe ground up into the skies.

Jackie is a great ambassador for all kinds of insects, whichshe swears are overwhelmingly beneficial and indeed “con-tribute more than we do” to the health of the planet.

Green darner dragonfly (Anax junius)

out their passion for bugs rs through the camera’s lens.

Experts by Bonnie Drexler, NEWFS Program and Volunteer Coordinator

Nose-to-nose with a butterfly


DON ADAMSHabitat Enhancer

Speaking with Don Adamsabout his passion for butterflies,bees, and moths, you onlynotice a few words of vocabu-lary that might indicate his“real” work as an electrical engi-neer. He “amplifies” results bycareful breeding of Baltimore

checkerspot butterflies. He constructs outdoor cages toprovide natural temperatures and “photoperiod” for thesilk moth cocoons he is protecting from raccoons andskunks. Other than these few technical terms, he soundstoday like the “buggy kid” he says he was growing up inSouth Weymouth,Massachusetts. Donand his wife, Cheryl,actively augmentpopulations of mothsand butterflies ontheir three-acreproperty in WestBridgewater,Massachusetts, byplanting the rightnative host plants.“You have to start with the plants—no plants, no butter-flies.” Then, when Don spots foraging caterpillars, he con-structs a cage around the plant or puts a sleeve on a stemto protect them from predators like birds, wasps, and flies.Their garden comes to resemble a “big science project” bythe end of the summer. The several dozen cages andsleeves need to be checked daily to keep them sanitary (byremoving frass) and to be sure there is still enough of theplant inside to be eaten. These efforts are aimed at tippingthe balance in favor of moths and butterflies in their area.

Don spreads his insect wealth by donating caterpillars andcocoons to friends, schools, and places like Garden in theWoods. The wildlife habitat that he and Cheryl have creat-ed on their property is great for all creatures—birds, bees,bugs, and people. “It’s all related,” says Don, “and it’s ahabitat for sharing.”

NAOMI PIERCECaterpillar Connections

For someone whoadmits she is “slightlyunsettled when con-fronted with largeinsects with hairy legs,”Naomi Pierce has devot-ed a lot of her life tounderstanding these life

forms. As Hessel Professor of Biology at HarvardUniversity and Curator of Lepidoptera at the Museum ofComparative Zoology, Pierce researches behavioral ecologyand species interactions, which often comes down to inves-tigating ant, caterpillar, and host plant associations in loca-tions around the world.

Of particular interest to Pierce and her students are butter-flies in the family Lycaenidae (blues, coppers, and hair-streaks). Although the Lycaenidae is only one of manyLepidoptera families, up to one third of endangered orthreatened butterflyspecies arelycaenids. The mostthreatened are thoseparasitic on ants. Insome relationships,ants act as guardsfor foraging cater-pillars in exchangefor a sugary sub-stance exuded fromspecial dorsal nec-tary organs on thecaterpillar’s body. Inother cases investi-gated in Australia,Pierce explains witha note of irony, caterpillars use a “brood pheromone” as akind of chemical camouflage to infiltrate the ant nest andfeast on the developing young. Some species of caterpillarhave even evolved a “cuckoo strategy” within the ant nest.Using chemical mimicry, they trick the adult ants intofeeding them mouth-to-mouth with regurgitated food.The complexity of these interactions, and as a conse-quence, their vulnerability to habitat loss, makes thelycaenids a sort of “canary in a coal mine” (much like thepitcher plants you read about on page 17) for environ-mental change.

Pierce’s interests extend from pure research to practicalapplication, from plant and pathogen relationships to lifehistory evolution. She focuses on the minutia of speciesinteractions but the lessons learned may someday extend to the health of our planet.

Tiger swallowtail (Papilio glaucus)

Io moth (Automeris io)

Ogyris genoveva caterpillar with a Camponotus sp. worker ant

The Dragon-fly

Today I saw the dragon-fly

Come from the wells where he did lie.

An inner impulse rent the veil

Of his old husk: from head to tail

Came out clear plates of sapphire mail.

He dried his wings: like gauze they grew;

Thro’ crofts and pastures wet with dew

A living flash of light he flew.

Alfred Lord Tennyson, 1833

LEARN MOREWhy the World Is Green by Elizabeth Farnsworth

Farrell, B. D. 1998.“Inordinate fondness” explained:Why are there somany beetles? Science 281: 555–559.

Hairston, N., F. E. Smith, and L. B. Slobodkin. 1960. Community struc-ture, population control, and competition. American Naturalist 94:421–425.

Labandeira, C. C. et al. 1994. Ninety-seven million years of angiosperm-insect association: Paleobiological insights into the meaning ofcoevolution. Proceedings of National Academy of Sciences 91:12278–12282.

The Mating Game by David Giblin

Buchmann, S. L. and G. P. Nabhan. 1996. The Forgotten Pollinators. IslandPress,Washington, D.C.

Kearns, C.A., D.W. Inouye, and N. M.Waser. 1998. Endangered mutu-alisms: the conservation of plant-pollinator interactions. AnnualReview of Ecology and Systematics 29: 83–112.

North American Pollinator Protection Campaign (http://www.nappc.org/)

Proctor, M., P. Yeo, and A. Lack. 1996. The Natural History of Pollination.Timber Press, Portland, Oregon.

The Xerces Society (http://www.xerces.org)

What’s the Buzz ... Planting a Bee Garden(http://gears.tucson.ars.ag.gov/na/bgardn.html)

Plant Herbivore Interactions by Greg Lowenberg

Berenbaum, M. R. 1990. Ninety-nine Gnats, Nits, and Nibblers. Universityof Illinois Press, Urbana, Illinois.

Eisner,T. 2003. For Love of Insects. Belknap Press, Cambridge,Massachusetts.

Waldbauer, G. 2003. What Good Are Bugs?: Insects in the Web of Life.Harvard University Press, Cambridge, Massachusetts.

Ants by Henry Art

Art, H.W. 2000,The finest fragments. New England Wild Flower 4: 26–27.

Hölldobler, B. and E. O.Wilson. 1990. The Ants. Belknap Press,Cambridge, Massachusetts.

Insects Raise Some Galling Questions by Warren Abrahamson

Abrahamson,W. G. and A. E.Weis. 1997. Evolutionary Ecology Across ThreeTrophic Levels: Goldenrods, Gallmakers, and Natural Enemies. PrincetonUniversity Press, Princeton, New Jersey.

Weis,A. E. and W. G.Abrahamson. 1998. Just Lookin’ for a Home.Natural History 107: 60–63.

The goldenrod and the gallfly: evolution of an interaction. 2001. 36-min.video.The Pennsylvania State Media Sales, University Park, PA. $25.

Virginia Cooperative Extension: Galls (http://www.ext.vt.edu/depart-ments/entomology/factsheets/galls.html)

Killer Plants of New England and Beyond by Elizabeth Farnsworth

Ellison,A. M. 2002. Food for thought: a review of recent research onpitcher-plant bogs in New England. Conservation Perspectives(http://www.nescb.org/epublications/summer2002/).

Life Down Under by Bruce Wenning

Samways, M. 1994. Insect Conservation Biology. Chapman and Hall, NewYork, New York.

Soil Foodweb, Inc. (http://www.soilfoodweb.com)

IPM: Integrated Pest Management by Bob Childs

Carson, Rachel, Silent Spring. (1962) 1994 reprint. Houghton MifflinCompany, Boston, Massachusetts.

Olkowski,W., S. Daar, and H. Olkowski. 1996. The Gardener’s Guide toCommon-Sense Pest Control. Taunton Press, Berkeley, California.

National IPM Network: Northeast Region: Integrated Pest Managementin the Northeast (http://northeastipm.org)

Ecological Landscaping by Cheryl Lowe

Ecological Landscaping Association (http://www.ela-ecolandscapin-gassn.org/index.htm)

Tiny Destroyer of Mighty Forests by Pam Thomas

Cornell Cooperative Extension: Hemlock Woolly Adelgid (http://www.cce.cornell.edu/suffolk/grownet/tree-insect/hemwool.html)

Fuller, J. L. 1998. Ecological impact of the mid-Holocene hemlockdecline in southern Ontario, Canada. Ecology 79: 2337-2351.

Lily leaf beetle, University of Massachusetts Extension(http://www.umassgreeninfo.org/fact_sheets/defoliators/lily_leaf_bee-tle.html)

Gypsy moth, USDA Gypsy Moth Handbook(http://www.fs.fed.us/na/morgantown/fhp/gm/gmhb.htm)

A Daydream Journey by Mike Nelson

Massachusetts Natural Heritage & Endangered Species Program,Rare Plants and Animals,(http://www.mass.gov/dfwele/dfw/nhesp/nhspecies.htm)

Image websites

USDA Forestry Images (http://www.forestryimages.org/)

Iowa State University Entomology Image Gallery (http://www.ent.ias-tate.edu/imagegallery/)

OfficersPresident–Elizabeth S. EustisVice President–Susan KearneyTreasurer–Lalor BurdickAssistant Treasurer–Christopher ElyClerk–Frances H. ClarkAssistant Clerk–Thelma HewittExecutive Director–David L. DeKing

Board of TrusteesClara BatchelorMolly S. BeardRuah DonnellyJane O. GoedeckeMarjorie GrevilleRob HeldSusanah B. HowlandChristopher LeahyJames MarzilliPeter H. MattoonKay McCahanGeorge McCully

David MittelstadtAnne MooreJessie PanekGeri PaynePolly PiercePatsy RabstejnekSara SilversteinJackie StoneMary Ann StreeterPatrick M.TynanTony Wain

New England Wild Flower Society

180 Hemenway Road,Framingham, MA 01701

508-877-7630 • TTY [email protected]

http://www.newfs.org

OverseersAnnemarie AltmanBerta AtwaterSally CookPeter V. K. DoyleCorliss Knapp EngleBarbara E. GrayPerry R. HagensteinChristina HobbsElsa HornfischerPatricia W. HustonStephen T. JohnsonJoy KuhnBetsy MadsenEllen B. McFarlandBob C. MitchellAndré J. NavezRuben D. OrduñaKaren PierceHatsy ShieldsLucy SurClaudia G.ThompsonCarrie WatermanMercy WheelerRobin WilkersonSusan Winthrop

Honorary TrusteesJohn D. ConstableEdward N. DaneSusan DumaineCatherine FarlowMarion HaffenrefferJane HallowellGeorge C. HarringtonAlice JonesDana N. JostDunbar LockwoodPennie LogemannDorothy S. LongEllen West LovejoyJohn LynchHelen NowersEsther Grew ParkerAdelaide M. PrattDaphne Brooks ProutBeverly RyburnNan St. GoarMuriel SouleGalen StoneGerard B.TownsendBunny TraylorMary M.WalkerRichard Weinberg

New England Wild FlowerConservation Notes of the

New England Wild Flower Society

Volume 8, No. 2, 2004

New England Wild Flower is published threetimes a year by the New England WildFlower Society, an independent, nonprofit,member-supported organization whosepurpose is to promote the conservation oftemperate North American plants througheducation, research, horticulture, habitatpreservation, and conservation advocacy.Subscriptions to New England Wild Flowerare included in membership dues which startat $42/year for individuals.

CREDITSPhotography:Arieh Tal–front cover (Monarch caterpillar[Danaus plexippus], p. 1, back cover (Monarchbutterfly on aster), 25 topAdelaide M. Pratt–inside cover, 17 top mid-dle, 18, 37Norman E. Rees, USDA ARS,www.forestryimages.org–p. 2 top leftJackie Stone–p. 3, 9 left, 11 top left, 20 top,33 top right, 33 bottomLisa Mattei–p. 4 top, 24, 26 top, 33 top leftJohn A. Lynch–p. 5 middle, p. 12 bottomleft, 20 bottomFrank Bramley–p. 5 bottomWilliam Larkin–p. 6 top twoDavid M. Stone–p. 6 middle & bottomright, p. 8, 16, 17 top right, 19 bottom left Dorothy S. Long–p. 6 bottom left,p. 7 left, p. 12 middle right, 35Greg Lowenberg–p. 7 middle rightLarry R. Barber, USDA Forest Service,www.forestryimages.org–p. 9 rightRichard A. Casagrande, University ofRhode Island, www.forestryimages.org–p. 11 rightHenry Art–p. 12 top left, 13 allWilliam Cullina–p. 12 bottom rightWarren G.Abrahamson–p. 14, 15 allexcept bottom rightKenneth McCrea–p. 15 middle right Chris Abrahamson–p. 15 bottom rightAlbert Bussewitz–p. 17 top leftGerald J. Lenhard, Louisiana StateUniversity, www.forestryimages.org–p. 17bottom leftJosef Mendelsohn–p. 17 bottom rightRobert L.Anderson, USDA ForestService, www.forestryimages.org–p. 19 topRonald M.Weseloh–p. 19 bottom middleDavid Stotzer–p. 19 bottom rightSteven Scrimshaw–p. 22 topDennis J. Souto, USDA Forest Service,www.forestryimages.org–p. 26Mike Nelson/MA NHESP–p. 28, 29 left,29 top right, 30Blair Nikula–p. 29 bottom rightDave Wagner–p. 32 allDon Adams–p. 34 all leftNaomi Pierce–p. 34 all right

Illustration:Susanah B. Howland–p. 22 & 23 bottom

This publication was made possible through the generosity

of Jackie and Tom Stone, The Millipore Foundation, and

members and friends of the New England Wild Flower Society.

Copyright © 2004 New England WildFlower Society®.All rights reserved.

No material in this publication may bereproduced or used in any way withoutwritten consent. For permission, contactEditor, New England Wild Flower,180 Hemenway Road,Framingham,MA 01701.

Monarch chrysalis (Danaus plexippus)

Executive Director/Editor in Chief:David L. DeKing

Managing Editor, Design, and Production:Lisa Mattei

Copy Editors: Sarah Shonbrun and Susan ThompsonEditorial Advisors: Elizabeth Farnsworth, GregLowenberg, and Cheryl LoweMarketing Director: Debra Strick

Special Thanks: Barbara Pryor for photo researchand Bob Christoph for proofreading services.Printing: LaVigne Inc.

Additional copies of this publication are available.For information, please contact the Museum Shop at 508-877-7630, ext. 3601 or www.newfs.org.

NON-PROFITORGANIZATION

U.S. POSTAGE PAIDPERMIT NO. 7ASHLAND, MA

New England Wild Flower Society180 Hemenway RoadFramingham, MA 01701-2699

ADDRESS SERVICE REQUESTED

Documents

New EnglandWildFlowerbackstage.newenglandwild.org/resources/conservation...2–New England Wild Flower W ith all the hungry, slavering, assiduous little insects out there, waiting