Invasive plants: identities, issues and

theory by Richard Gardner

Oriental bittersweet Purple loosestrife Japanese knotweed

Winged euonymus

Multiflora rose

Wineberry

Amur honeysuckle

Japanese honeysuckle

Russian olive

Oriental bittersweet

Terminology

and

Basic Concepts

Backyard ecology/backyard research – most of the important research in ecology can literally be done in our back yards. All the relationships and answers to the big questions are there for us to find. Exotic locations and expensive equipment only confirm what we already observed and synthesized.

Every slide in this presentation was taken within 30 miles of home. Most were taken within 10 miles with some in our backyard. All the basic concepts were developed while walking near home. Total expenses to do this and related research is less than $3000 over 4 years, including consumables. The most expensive pieces of equipment are the computer and the camera.

Medicating the ecology - My first fear with biocontrols is that we select target organisms the way we select any other problem that appears to need solving. We look only at the crisis. Then we charge in solving an apparent problem mechanistically without looking in depth to understand the crisis or look for creative minimally disruptive or less dangerous alternatives.

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Non-native specialist biocontrol

Non-native invasive Chemical defenses of non-native invasive population

time

This diagram demonstrates what happens when a non-native specialist biocontrol is reintroduced to its non-native host such as with wild parsnip, Senecio jacobaea. When Tyria jacobaeae, one of its specialist biocontrols from Europe was accidently reintroduced after at

least 230 years

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Non-native biocontrol

Non-native invasive

Native congeners and conspecifics of non-native invader

time

Simplified expected curves for what happens when a non-native biocontrol is introduced after the establishment of a non-native invasive due to the

biocontrol adapting to new food sources without defenses to that biocontrol.

Classical biocontrol – the introduction of non-native organisms in the attempt to reduce the effects of other introduced non-native organisms on ecosystems. At the same time there are unforeseen negative effects which cannot be predicted in the local and extra-local ecosystems in which they are introduced through genetic or behavioral changes in the non-native biocontrol and in native organisms.

In other words it is a mechanistic attempt to use non-native organisms to control already present non-native organisms. It does not attempt to bring an ecosystem back into balance. Instead it causes a new system and (im)balance to develop that is inherently alien.

Non-native biocontrol has high rates of failure

and low rates of success, an average of 2.44

introduced organisms for every species on

which control is being attempted. I think this

number is underestimated and that the real

number is at least 5 introduced organisms for every biocontrol target.

Bioeradication – The extinction of a non-native (invasive) species from an ecosystem using native organisms. The goal is the regeneration of the ecosystem by eliminating the non-native problem from the ecosystem using native organisms which minimize the potential problems associated with the addition of non-native organisms as potential controls.

Bioeradication uses a variety of native organisms working together to eradicate a non-native organism from the ecosystem and restore it to its original state.

The difference between bioeradication and biocontrol is that bioeradication assumes it is possible to eradicate a non-native species from an ecosystem using native species. While biocontrol is trying to change, modify or minimize the effects of one non-native organism by using another non-native organism.

Bioeradicant – Any native organism in any time frame from seconds to centuries that partially or fully inhibits a non-native organism and helps to drive it to extinction.

Bioeradication system – A group of native organisms which through any biological relationship and time frame partially or fully inhibits a non-native organism to the point it is driven to extinction.

Hybrid bioeradication system – A group of native and indigenous non-native organisms which through any biological relationship and time frame partially or fully inhibits a non-native organism to the point it is driven to extinction.

Direct bioeradication – This is the use of a native organism or native organism system as a bioeradicant for a specific organism.

Indirect bioeradication – Providing the native resources such as food, breeding sites or shelter needed for a native bioeradicant or bioeradicant system to develop at a specific location for a specific organism. This may be nectar sources, sheltering plants, mutualistic fungi, water source or … .

Bioremediation – the use of native organisms to displace and eradicate non-native organisms or to replace non-native organisms as they are eliminated from an ecosystem. This is an expansion of the traditional definition of bioremediation. Whereas, traditional bioremediation is the use of microorganisms or plants to mitigate chemical or organic pollution. This is the use of the term to mean use of native organisms to restore an ecosystem during the process of and after the removal of a non-native organism or non-native organism system.

The question most frequently asked with Bioeradication is why has no one noticed it before?

The answer is twofold:

1.) no one thought to look

2.) many of the non-natives were eradicated before anyone even noticed they were around or an issue.

To further this argument, the first plant I investigated, Ailanthus altissima, had a complete bioeradication system. If my first target proved that bioeradication is happening, imagine how many other invasives are undergoing the same.

Some of the local invasive non-native

plants

Common name: Tree-of-heaven Scientific name: Ailanthus altissima Origin: China Local habitat: It prefers the edge of wooded areas and open fields. However, it will grow in wooded areas where light reaches the forest floor. Reproduction: This tree is dioecious with separate male and female trees. A mature female may produce over 350,000 seeds/year. Germination rate may run as high as 90% under controlled conditions. When mechanically (physically) injured, this tree will produce many clones from its roots up to 30 yards away. Seed bank is one year except under controlled conditions. Identifying features: It has odd pinnate compound leaves with opposite blade-like leaflets. Leaflets have one pair to several pairs of notches along the edge of the proximal end. Each notch has a gland on the distal end of the point. The odor is unmistakable at certain times when downwind. Weaknesses: tends to form monoclonal stands when physically injured and may interconnect roots between individuals in a stand. This means that herbivores and disease have fewer genotypes to deal with and disease can move through root grafts within the stand. It is dioecious with possible sterilization of female trees. Local Controls: A combination of the native moth Atteva aurea, the eriophyoid mite Aculops ailanthii, various as of yet unidentified herbivorous insects and several pathogenic Fusarium and Verticillium fungi. Whitetailed deer browse leaves. Outlook: Apparently slowly going extinct locally and probably throughout its eastern North American range from naturally occurring processes..

Common name: Tree-of-heaven Scientific name: Ailanthus altissima Origin: China Local habitat: It prefers the edge of wooded areas and open fields. However, it will grow in wooded areas where light reaches the forest floor. Reproduction: This tree is dioecious with separate male and female trees. A mature female may produce over 350,000 seeds/year. Germination rate may run as high as 90% under controlled conditions. When mechanically (physically) injured, this tree will produce many clones up to 30 yards away. Identifying features: It has odd pinnate compound leaves with blade-like leaflets which are opposite. Leaflets have one pair to several pairs of notches along the edge of the proximal end. Each notch has a gland on the distal end of the point. The odor is unmistakable at certain times when downwind. Weaknesses: tends to form monoclonal stands when physically injured and may interconnect roots between individuals in a stand. This means that herbivores and disease have fewer genotypes to deal with and disease can move

through root grafts when spreading through a stand. Local Controls: A combination of the native moth Atteva aurea, Aculops ailanthii, various as of yet unidentified herbivorous insects and several pathogenic Fusarium and Verticillium fungi. Whitetailed deer browse leaves. Outlook: Apparently slowly going extinct locally and probably throughout its eastern North American range from naturally occurring processes.

Very early in the life of Ailanthus the main root makes a right angle turn that is parallel with the ground as seen in this photo and the following.

male flowers due to prominent stamens and minimized pistils

glands

male tree

female tree

July 29, 2013

August 1, 2012

July 17, 2013

September 5, 2013

September 23, 2013

Atteva aurea, a native moth

A female Atteva aurea depositing eggs on a community web.

Aculops ailanthii, an eriophyoid mite

Mite experiment at home that ended on Nov. 19, 2013

Mites from mite experiment at home that ended on Nov. 19, 2013

Fusarium micro and macroconidia from diseased tree.

Fusarium lateritium macroconidia

Birds – best for long distances between

landscapes

Moths – best for medium and short distances within a

landscape

Wind – best within

landscapes for short distances with high

mite and tree densities

Transport of Aculops ailanthii and disease across landscapes

From recent walking it appears that there is a correlation between the density and nearness of the nectar sources adult Atteva aurea feed on

and the amount of disease in a stand of Ailanthus.

Rudbeckia laciniata

Monarda fistulosa

Leucanthemum sp.

Solidago sp.

Ailanthus altissima

bioeradication garden

Ailanthus altissima bioeradication garden

2. Aster laevis 1. Asclepias tuberosa

4. Erigeron speciosus 3. Aster novae-angliae

6. Eupatorium perfoliatum 5. Eupatorium maculatum

8. Monarda fistulosa 7. Heliopsis helianthoides

10. Rudbeckia laciniata 9. Rudbeckia hirta

12. Solidago canadensis 11. Rudbeckia triloba

14. Solidago rigida 13. Solidago nemoralis

16. Verbesina alternifolia 15. Solidago speciosa

18. sunflowers 17. Asclepias syriaca

19. Coreopsis 20. Shasta daisy

21. sweet peppers 22. sweet peppers

23. sweet peppers 24. Eu. mac./Cor. trip./Ech. pur.

25. Collected plants

pasture uphill driveway

Common name: Multiflora rose Scientific name: Rosa multiflora Origin: Asia Local habitat: fields and wooded areas Reproduction: seeds and stem clones Identifying features: the only local rose I know of where the thorns curve towards the center of plant Weaknesses: Many native and non-native relatives from which disease and herbivores can evolve to become bioeradicants. Dense stands facilitate the spread of herbivores and disease. Birds eat the abundant fruit, potentially spreading disease and herbivores between plants locally and across landscapes. Clonal growth limits genetic heterogeneity and facilitates the movement of disease through a stand. Local Controls: Rose rosette disease, an Emaravirus spread by the eriophyoid mite Phyllocoptes fructiphilus is in a bioeradication system with birds. It probably developed on a native rose in California or another Pacific Coast state. Outlook: Fantastic. It is severely affected by rose rosette disease and possibly another disease which yellows the leaves.

Probable scenario for the spread of rose rosette disease across the ecosystems

Birds – carrying mites long distances, between landscapes

Pollinators – carrying mites medium distances, within landscapes

Wind – carrying mites short distances, within stands

Common name: Japanese honeysuckle Scientific name: Lonicera japonica

Origin: Asia

Local habitat: It prefers the edge of wooded areas and open woodlands.

Reproduction: Cloning and bird distributed seeds.

Identifying features: Lancelet shaped leaves opposite on climbing vines. Distinct flowers with a sweet odor when in bloom. Prefers shaded edges with a substrate of brush and small trees to climb on.

Weaknesses: Many native and non-native relatives from which disease and herbivores can evolve from to become bioeradicants. Clonal spread limits genetic heterogeneity and is a pathway for disease to move through a stand. Birds eat the abundant fruit, potentially spreading disease and herbivores between plants locally and across landscapes.

Local Controls: There appears to be beetle herbivory and several diseases which it shares with other non-native bush honeysuckles.

Outlook: This plant is on the decline from my observations due to disease and insect herbivory. It should be an easy research target for bioeradication.

Common name: Morrows honeysuckle Scientific name: Lonicera morrowii Origin: Asia Local habitat: wooded areas Reproduction: seeds spread by birds Weaknesses: Many native and non-native relatives from which disease and herbivores can evolve to become bioeradicants. Dense stands facilitate the spread of herbivores and disease. Birds eat the abundant fruit, potentially spreading disease and herbivores between plants locally and across landscapes. Identifying features: Bushy shrub with lancelet leaves similar to Japanese honeysuckle. Local Controls: Herbivorous insects with mites and disease working together. I am seeing possibly three separate diseases as I walk. Outlook: Going extinct throughout its eastern North American range due to disease and herbivory.

May 15, 2013

June 19, 2013

July 25, 2013

August 7, 2013

August 26, 2013

September 4, 2013

October 3, 2013

Probable scenario for the movement of pathogens and insect herbivores between

Lonicera morrowii plants.

Wind – short distances within landscapes Deer – short and medium

distances between thickets within a landscape

Birds – long distances between landscapes

Insect pollinators and herbivores – short and medium distances within a landscapes

Common name: Amur honeysuckle Scientific name: Lonicera maackii Origin: Asia Local habitat: wooded areas Reproduction: seeds spread by birds Identifying features: blade shaped leaves with a curved narrowing point Weaknesses: Many native and non-native relatives from which disease and herbivores can evolve to become bioeradicants. Dense stands facilitate the spread of herbivores and disease. Birds eat the abundant fruit, potentially spreading disease and herbivores between plants locally and across landscapes. Local Controls: Herbivorous insects with mites and disease working together. I am seeing a variety of separate diseases as I walk. Outlook: Going extinct throughout its eastern North American range due to disease and herbivory.

Common name: Grape hyacinth Scientific name: Muscari sp. Origin: Europe Local habitat: wooded areas primarily near old homesteads Reproduction: seed and bulb Identifying features: clusters of blue to purple flowers on a single stem Weaknesses: flowers and fruits are not used by many if any animals or birds. Flowers are self-pollinating and much of the reproduction is done asexually so the amount of genetic heterogeneity in a patch is limited. Dense patches encourage disease and herbivory. Local Controls: none Outlook: This is worth watching as I saw it spread down a trail due to hitchhiking seeds. It could become a problem starting around homesteads, but spreading across a landscape.

Part of the mile of trail where an infestation has spread from an abandoned

home.

Common name: Periwinkle Scientific name: Vinca minor Origin: Europe, Asia Local habitat: wooded and partially wooded old homesteads Reproduction: seeds and vines Identifying features: low growth along the ground on woody vines, shiny evergreen ovate leaves, blue 5 petal flowers. Weaknesses: Tends to move slowly across landscapes. Dense patches facilitate the spread of herbivores and disease. Local Controls: none obvious Outlook: It is mostly invasive near where it was planted, seldom travels far. This will hopefully prevent if from becoming more than a local problem wherever it is found.

start of infestation

end of infestation, @ 200 yards from start

Common name: Japanese stiltgrass Scientific name: Microstegium vimineum Origin: Asia Local habitat: wooded areas with partial sun. It usually starts along the edge of trails and roads where people accidently carry the hitchhiking seeds and spreads from there. Intermittent/seasonal streams are often a preferred growing location and a corridor by which it spreads into the forest. Reproduction: seeds Identifying features: silver vein down middle of leaf, large dense stands which become noticeable in late summer Weaknesses: Many native and non-native relatives from which disease can evolve into a bioeradicant. Tends to grow in well-traveled areas which facilitates the spread of disease. Local Controls: members of the Bipolaris fungi family that may have evolved from native pathogenic fungi of Zea mays. Outlook: The short term is bad by the rate at which this weed spread. However, in the long term as is happening in the Midwest, it should be eradicated by Bipolaris fungi.

Common name: Canada thistle Scientific name: Cirsium arvense Origin: Eurasia Local habitat: open fields Reproduction: seeds and clones Identifying features: Purple flower sits on top of a vase shaped flower head. Low growing spiky blue green leaves in a floret when early in a growth cycle. Weaknesses: Many native and non-native relatives from which disease and herbivores can evolve to become bioeradicants. Dense patches facilitate the spread of herbivores and disease. Clonal growth allows disease to spread through a patch without genetic heterogeneity . Local Controls: There are no effective controls at this time. However, it is the “poster child” for what not to do with a non-native biocontrol.* Goats may be the best way of controlling this plant in a pasture or open field. Outlook: No local control is in sight even though this is part of a large family with the potential to develop bioeradicants. NOTE: *Rhinocyllus conicus was introduced to control this weed. Instead it went rogue and started eating native thistles.

Common name: Mile-a-minute Scientific name: Polygonum perfoliatum Origin: Asia Local habitat: edges of woods and open areas within woods Reproduction: seed Identifying features: blue green triangular leaves, fuchsia/green prickly stems, blankets an area fast Weaknesses: Many native relatives from which disease and herbivores can evolve to become bioeradicants. Self pollinating. Dense stands facilitate the spread of herbivores and disease. Birds eat the abundant fruit, potentially spreading disease and herbivores between plants locally and across landscapes. Not tolerant to cold/frost so dies if there is a late spring frost or an early fall frost. Limited growing season in cooler areas, reducing size of plants and seed production. Local Controls: none, the non-native biocontrol appears to be failing. There is the possibility that a disease is beginning to infect this plant. Outlook: This plant is in a large family of related plants. Therefore, I expect it to go extinct when native organisms catch up with it. I found it infesting a woodland near the University of Delaware, the place where non-native biocontrols are being studied and released in attempts to control it. This suggests that the non-native biocontrol is failing.

After frost with Ailanthus altissima

Example of plants with similar physiology in close proximity to P. perfoliatum.

Example of plants with similar physiology in close proximity to P. perfoliatum.

http://www.clker.com/clipart-eastern-u-s-map.html

States with Mile-a-minute and expected short term trajectory

Collection

My first concern with this plant is that propagule spread is an important component of how problems develop. With Mile-a-minute, it is obvious that migrating birds are already spreading the seeds along the species specific eastern United States migration corridors. This makes the plant a bad target for biocontrol as the plant spreads too rapidly and too far. Unless a bioeradicant system develops, this plant will continue to spread without any hope of containing or eradicating it.

My second concern with Mile-a-minute biocontrols is the same as with most, a non-native biocontrol brought in that goes rogue and starts eating natives.

Testing of biocontrols is necessarily limited to try to control the number of variables, reduce time to release and reduce costs. This unfortunately increases the probability that the biocontrol will attack native plants and/or otherwise disrupt the ecosystem.

The basis of this concern is threefold:

1.) too few native conspecifics, congeners, confamilials are tested.

2.) too few generations of native plant/biocontrol interactions are tested, which do not represent ecological reality.

3.) plants with similar physical shape and other attributes are not tested, especially those in close proximity to the target plant in the field.

Which leads me to fear that due to the limited understanding of the long term ecological relationships and the narrow numbers of organisms tested with the short time frame of testing, biocontrols will jump from their targeted plant to others, especially natives related by genes, physical attributes and proximity.

My prediction is that the biocontrol, Rhinoncomimus latipes, introduced for this plant will begin going rogue within the next few years if it has not already.

Common name: Oriental bittersweet Scientific name: Celastrus orbiculatus Origin: Asia Local habitat: forests and fields Reproduction: seeds Identifying features: acuminate leaves towards and on the ends of new growth becoming orbicular mature leaves, bright yellow/orange seeds in the fall. Vine is not hairy as is poison ivy or shaggy like native grape. Weaknesses: A close native relative from which disease and herbivores can evolve to become bioeradicants. Dense stands facilitate the spread of herbivores and disease. Birds eat the abundant fruit, potentially spreading disease and herbivores between plants locally and across landscapes. Local Controls: None now. However, a disease was apparently forming at home on the leaves of several plants. Outlook: In time since it has a close native relative, I expect a native organism or more probably organism system to begin to eradicate it.

Common name: Wineberry Scientific name: Rubus phoenicolasius Origin: Asia Local habitat: woodlands, along the edges of road roads and trails Reproduction: seeds and clones from stems Identifying features: hairy red or green stems with a combination of soft fuzzy prickles and hard thorns. Stems turn red in the fall. Fruit forms in pods which break open about a week before ripening to clusters of bright red drupelets. Weaknesses: Many native and possibly non-native relatives from which disease and herbivores can evolve to become bioeradicants. Clonal stands facilitate the spread of herbivores and disease. Birds eat the abundant fruit, potentially spreading disease and herbivores between plants locally and across landscapes. Local Controls: When I walk there appears to be disease and herbivory similar to native blackberries and the native raspberries for which it was brought in to hybridize with. Outlook: Positive as I see disease and herbivory which appears to have moved from closely related native raspberries.

Native raspberry showing disease which may be in the process of being passed to non-native

wineberry.

Common name: Garlic mustard Scientific name: Alliaria petiolata Origin: Eurasia Local habitat: the understory along trails and roads Reproduction: seeds Identifying features: it is one of the earliest forbs to bloom which has white flowers on multiple stems up to mid-thigh high. According to Bernd Blossey of Ithaca College, it needs earthworms to flourish so it will usually not be found where earthworms have not been introduced. Weaknesses: A member of a large family of native and non-native plants from which diseases and herbivores can evolve to become bioeradicants. Local Controls: Since it is in the mustard family, there are potential native bioeradicants developing. Humans can help by picking it for flavoring hopelessly boring English/German style cooking and as a nutrition source. Outlook: Positive as there is an apparent bioeradicant already beginning to make an impact and many native plants within the family.

Common name: Japanese barberry Scientific name: Berberis thunbergii Origin: Asia Local habitat: the understory and along the margins of wooded areas Reproduction: Seeds eaten by birds Identifying features: thorns on woody stems, with red leaves and red berries in the fall on a generally low growing shrub in the understory of a forest or along its edges. Weaknesses: Dense patches facilitate the spread of herbivores and disease. Birds consume the seeds potentially spreading herbivores and disease across small and large landscapes. Local Controls: none at this time except allowing the native understory deprive it of light by control of Whitetailed deer. Outlook: At best pessimistic for now unless deer are controlled. I continue to look at this plant with hope. Our best action is to have the Pennsylvania Game Commission stop trying to manage the deer herd for hunting and start managing it for conservation. This includes stopping hunting of predators such as coyotes, which will naturally reduce the size of the deer herd.

Common name: Winged burning bush Scientific name: Euonymus alatus Origin: temperate Asia Local habitat: wooded areas as an understory plant Reproduction: seeds Identifying features: understory shrub with leaves which turn a bright red in the fall, green irregularly shaped stems with brows “wings” on them Weaknesses: dense patches facilitate the spread of herbivores and disease. Local Controls: none I see so far, but I am looking Outlook: The one dense patch I know of, Skinners Loops in Blue Marsh, appears to show no signs of disappearing anytime soon. At the same time, I was shocked now that the foliage has turned red to see just how many of these plants are around. The best action is to remove these plants from nurseries and yards to stop the introduction of these plants to places where they are not yet.

Common name: Purple loosestrife Scientific name: Lythrum salicaria Origin: Eurasia Local habitat: wetlands, the borders of streams and lakes Reproduction: seed Identifying features: wetland plant with long spikes of purple flowers Local Controls: none I am aware of Weaknesses: Dense stands facilitate the spread of herbivores and disease. Pollinators visit often, potentially spreading disease and herbivores between plants locally and across landscapes. Outlook: One of the non-native biocontrols apparently may have taken a liking to a native plant and gone rogue. Otherwise in time, I expect this plant to have herbivorous insects and diseases use it as an energy source as there are native relatives.

Common name: Common teasel Scientific name: Dipsacus fullonum Origin: Europe Local habitat: Open fields Reproduction: seed Identifying features: tall spiky stems with lavender inflorescences at the end during the summer Weaknesses: Dense stands facilitate the spread of herbivores and disease. Pollinators can spread disease and herbivores throughout local dense stands and across landscapes. Local Controls: none I know of Outlook: I have not extensively studied this plant yet, but expect a bioeradication system to eventually develop.

Common name: Crown vetch Scientific name: Coronilla varia Origin: Penn State Department of Agriculture, Mediterranean basin Local habitat: open fields and spaces Reproduction: seeds Identifying features: low lying ground cover with compound like leaves and red/lavender/pink flowers Weaknesses: Close native and non-native relatives from which disease and herbivores can evolve to become bioeradicants. Dense stands facilitate the spread of herbivores and disease. Local Controls: none I am aware of Outlook: Since Penn State introduced it, there may be a considerable time before a native system overwhelms it. However, because it is a legume, there should be ample bioeradicants available which may adapt to it as an energy source. I am especially expecting a fungus/beetle or a fungus/nematode system to develop from the Fabaceae family.

Common name: Spotted knapweed Scientific name: Centaurea stoebe Origin: Eastern Europe, probably through contaminated seed Local habitat: open fields and trails Reproduction: seed Identifying features: proliferate small purple to lavender loosely thistle-like flowers on multiple branches, blue-green pinnatisect ground level foliage resembles lance- leafed Coreopsis Weaknesses: Dense stands facilitate the development and spread of herbivores and disease. Pollinators can spread disease and herbivores throughout local dense stands and across landscapes. Local Controls: none Outlook: This is another plant I have not really studied although I have seen thousands of them.

Common name: Lesser Celandine Scientific name: Ranunculus ficaria Origin: Europe Local habitat: wooded flood plains Reproduction: seeds and roots/bulbs Identifying features: bright low to the ground yellow flowers in thick green broad-leafed clumps in the spring. Weaknesses: Many close native and non-native relatives from which disease and herbivores can evolve to become bioeradicants. Dense stands facilitate the spread of herbivores and disease. Local Controls: none Outlook: Since it is a ranunculus with many relatives, there is hope.

Common name: Privet Scientific name: Ligustrum sp. Origin: Europe Local habitat: understory and edges of wooded area Reproduction: seeds Identifying features: a shrub with leaves which are even opposite and superficially similar to Burning Bush, but stems are roundish and foliage does not turn bright red in the fall. Weaknesses: Many native and non-native relatives from which disease and herbivores can evolve to become bioeradicants. Dense stands facilitate the spread of herbivores and disease. Birds eat the abundant fruit, potentially spreading disease and herbivores between plants locally and across landscapes. Local Controls: none that I see at this time. Outlook: As with many other plants, in time I expect a system will develop which will use this plant as an energy source.

Common name: Dames rocket Scientific name: Hesperis matronalis Origin: Europe Local habitat: open woodland Reproduction: seed Identifying features: light purple, deep purple and white flowers on a daisy-like stem which blooms in mid-spring Weaknesses: Close native and non-native relatives from which disease and herbivores can evolve to become bioeradicants. Dense stands facilitate the spread of herbivores and disease. Local Controls: none Outlook: I am uncertain with this plant as it was established early in the period of European settlement and is now naturalized ornamental flower.

Common name: Russian olive Scientific name: Elaeagnus angustifolia Origin: Europe Local habitat: the edges of fields and open fields, often forming hedgerows Reproduction: seed Identifying features: It is a large dense shrub with silvery leaves. In the spring the flowers have a cloying scent. It has fewer thorns than its relative Autumn Olive (Elaeagnus umbellata). Weaknesses: Probably clones from only a couple individuals originally introduced resulting in limited genetic heterogeneity. When a disease or herbivore begins to use this as a food source this shrub has limited genetic tools from which to defend itself. Local Controls: none yet Outlook: My hope is that this shrub will go down in the future due to a native insect/disease combination. At the same time I hope that whitetail deer begin to heavily browse the foliage.

Common name: Chinese lespedeza Scientific name: Lespedeza cuneata Origin: Asia and eastern Australia Local habitat: dry areas with full sun Reproduction: seeds Identifying features: It resembles many plants common to dry areas. The long stems are covered with small dense light green leaves coming from the central bottom part of the plant. Weaknesses: A member of a large family of plants including many native ones, both ornamental and food crop, from which diseases and herbivores can develop. Stands tend to be dense which facilitates the spread of disease and herbivores. Local Controls: none yet Outlook: This plant may have local relatives. If so, my expectations are that given enough time and no human interference we should see this plant decline in the near future.

Common name: Porcelainberry Scientific name: Ampelopsis brevipedunculata Origin: China Local habitat: woods edges Reproduction: seed and root clones Identifying features: vining plant with distinct berries Weaknesses: As a member of the grape family there are numerous native and especially non-native relatives locally which can serve as sources of herbivorous insects and disease. Dense stands encourage herbivores and diseases to collect and evolve into potential bioeradicants. Local Controls: competition from other non-native invasive plants Outlook: It is uncertain as it is not common where I walk. So I have not studied it yet. However, since it is related to native and fussy non-native wine grapes and Virginia Creeper, this plant should be studied in depth to see if natives or accidently imported non-natives are using it as an energy source.

Common name: Japanese hops Scientific name: Humulus japonica Origin: China Local habitat: open fields and woodland borders with sufficient light Reproduction: seeds Identifying features: prickly cucumber-like vines with cone shaped flowers and seed heads Weaknesses: This plant needs full sun to grow best and generally moist soils. Shade may kill it. There are several native and non-native relatives which may serve as a source of disease and herbivores. Dense patches of nearly identical plants will encourage herbivory and disease to develop into bioeradicants. Local Controls: none I know of Outlook: It is not a species I have yet paid much attention to because it is not common. However, reviewing photographs from last year, there appears to be insects and fungi using it. At home, beer hops have been hammered by powdery mildew which may make the jump to this plant.

Common name: Stinging nettle Scientific name: Urtica dioica Origin: Eurasia, some similar species may be native Local habitat: wet areas Reproduction: seeds and clones from roots Identifying features: hairy stem which stings for hours or days when touched and distinct hanging flowers Weaknesses: Dense monocultural stands in wet areas with partial sun limit its range in a landscape and encourage herbivores and diseases to develop. Native relatives also encourage the development of bioeradicants. Local Controls: apparently at least one moth species uses this as a larval food Outlook: I have not studied it enough to know If anything uses it enough for food. Humans can boil and eat it as a nutritious food.

Common name: Asian or Orange daylily Scientific name: Hemerocallis fulva Origin: Asia Local habitat: mostly damp areas locally Reproduction: seeds and root clones Identifying features: the most common roadside daylily, medium orange flowers Weaknesses: reproduction by clones in dense clumps limiting genetic heterogeneity. Local Controls: none obvious Outlook: This plant has been around locally a long time, but has a few issues which may cause it problems in the future such as most of the reproduction is by roots which tend to not spread far at any one time.

Common name: Perilla Scientific name: Perilla frutescens Origin: Asia Local habitat: moist but not wet woodlands as part of the understory Reproduction: seeds Identifying features: square stem like in all mints, purple flowers, broad toothed leaves Weaknesses: it is a member of the mint family which has issues with herbivores and fungal infections. Local Controls: I am looking at the same powdery mildews that affect other mint family members Outlook: Hopeful since it is in a family that contains many local native and non-native relatives.

A bioeradicant may come from this plant, Monarda fistulosa.

Common name: Common reed Scientific name: Phragmites australis Origin: Eurasia Local habitat: fresh and brackish wet areas, pollution tolerant Reproduction: seeds and clones Identifying features: tall reed with a flag on top. It is supposed to be taller than the “native” species. Weaknesses: Several controls have been slowly moving here from the rest of its huge range. Large dense stands of clones limit genetic heterogeneity and make it a target for herbivorous insects and diseases. Local Controls: a few insects use the plant for food Outlook: My expectation is that within 50 years, this plant will be heavily beaten back due to accidental importation of herbivores and diseases from Eurasia and native organisms developing a taste for it. It has potential for commercial use in products requiring easily harvestable fiber.

Common name: Japanese knotweed Scientific name: Fallopia japonica Origin: Asia Local habitat: wetlands, along streams and rivers Reproduction: mostly asexual from pieces of rhizomes and stems, some possibly by seed Identifying features: huge beds of canes with broad spear-head shaped leaves, inflorescences of white flowers at the end of stems when in bloom Weaknesses: Dense stands of clones limit the genetic heterogeneity making it an easy target for herbivorous insects and disease. Local Controls: none now Outlook: There appears to be a start to disease and herbivory. Since this grows in dense clonal stands, I expect it to begin to have visible problems in the near future.

Addendum

THEORY

Walk more.

Tinker less.

As an ecologist, I regularly work with an almost infinite set of variables. To even attempt to reduce this huge set of variables into a few easily measured and understood is insanity,

while being morally and ethically wrong because it is not an accurate portrayal of reality and can

lead to disastrous consequences.

Biocontrol vs. Bioeradication Medicating the ecology vs. understanding and

working with it

Medicating the ecology - My first fear with biocontrols is that we select target organisms the way we select any other problem that appears to need solving. We look only at the crisis. Then we charge in solving an apparent problem mechanistically without looking in depth to understand the crisis or look for creative minimally disruptive or less dangerous alternatives.

The same misguided attitudes which we experience in medicine we experience in

ecology, everything needs fixing immediately.

We are constantly try to fix everything without first understanding what we are trying to fix.

Classical biocontrol – the introduction of non-native organisms in the attempt to reduce the effects of other introduced non-native organisms on ecosystems. At the same time there are unforeseen negative effects which cannot be predicted in the local and extra-local ecosystems in which they are introduced through genetic or behavioral changes in the non-native biocontrol and in native organisms.

In other words it is a mechanistic attempt to use non-native organisms to control already present non-native organisms. It does not attempt to bring an ecosystem back into balance. Instead it causes a new system and (im)balance to develop that is inherently alien.

Non-native biocontrol has high rates of failure

and low rates of success, an average of 2.44

introduced organisms for every species on

which control is being attempted. I think this

number is underestimated and that the real

number is at least 5 introduced organisms for every biocontrol target.

Bioeradication – The extinction of a non-native (invasive) species from an ecosystem using native organisms. The goal is the regeneration of the ecosystem by eliminating the non-native problem from the ecosystem using native organisms which minimize the potential problems associated with the addition of non-native organisms as potential controls.

Bioeradication uses a variety of native organisms working together to eradicate a non-native organism from the ecosystem and restore it to its original state.

The difference between bioeradication and biocontrol is that bioeradication assumes it is possible to eradicate a non-native species from an ecosystem using native species. While biocontrol is trying to change, modify or minimize the effects of one non-native organism by using another non-native organism.

Bioeradicant – Any native organism in any time frame from seconds to centuries that partially or fully inhibits a non-native organism and helps to drive it to extinction.

Bioeradication system – A group of native organisms which through any biological relationship and time frame partially or fully inhibits a non-native organism to the point it is driven to extinction.

Hybrid bioeradication system – A group of native and indigenous non-native organisms which through any biological relationship and time frame partially or fully inhibits a non-native organism to the point it is driven to extinction.

Direct bioeradication – This is the use of a native organism or native organism system as a bioeradicant for a specific organism.

Indirect bioeradication – Providing the native resources such as food, breeding sites or shelter needed for a native bioeradicant or bioeradicant system to develop at a specific location for a specific organism. This may be nectar sources, sheltering plants, mutualistic fungi, water source or … .

Bioeradication garden – A form of Indirect Bioeradication which is a garden of local native plants that provide a resource at any life stage that a native bioeradicant needs to be effective as a bioeradicant such as food, egg laying sites, overwintering sites, protection from predators, …, .

Presently we have an experimental bioeradication garden in our yard to determine nectar sources used by Atteva aurea.

Bioeradication resource – Any naturally occurring environmental resource a native bioeradicant needs to be effective as a bioeradicant.

Resource use – This is the use by a native bioeradicant of a native or non-native resource. In the case of a non-native resource it takes time to adapt to using it through either learning to use it (behavioral changes) or genetic changes, often both.

Resource familiarity – This is the amount of use of a resource by a native bioeradicant. In the case of non-native (invasive) resources time is required for a native bioeradicant to adapt to a non-native through either behavioral or genetic changes and begin driving the non-native to extinction.

Resource heritage – This is the passing on of a behavioral and/or genetic adaptation to a resource by a native bioeradicant. This can be through learning, by genetic change or more probably a combination of both. It can spread through a species horizontally as one organism learns from another or vertically as it is passed on to/through offspring through learning or genes.

Herbivory, predation and parasitism – Relationships in which one organism or groups of organisms benefit by using other organisms as an energy source. This does not imply that all the benefit accrues to the herbivore, predator or parasite as there are often unseen benefits to both groups of organisms.

Direct competition – When an organism competes directly with another organism for a resource. Examples are two species of bees competing for a nectar source or a vulture and a crow competing for an animal carcass. This is good if a native bioeradicant is successfully outcompeting a non-native organism, driving it to extinction. It is bad when a non-native is driving a native to extinction.

Positive indirect competition –Positive when an organism provides a resource needed for a native organism to compete with a non-native organism. Knowing how to manipulate this is better than introducing a non-native organism into an ecosystem to control another non-native organism. An example is providing plants as egg laying sites for a native butterfly that competes for nectar with a non-native species such as the cabbage butterfly.

Indirect Bioeradication can be a result of this.

Negative indirect competition - Using a native organism to destroy a biological resource that a non-native organism needs which is in competition with that or another native organism. This may be planting tall native wildflowers in a meadow to destroy a grass needed by a non-native moth for food, egg laying sites or shelter.

Resource enhancement/depletion – This is enhancing a resource needed by a native bioeradicant or depleting a resource needed by a non-native to help eradicate a non-native species.

This may be as simple as removing a dam to allow fish to migrate along a river corridor, adding stepping stones in a creek to facilitate drinking by native animals or changing a dry meadow back to a flooded meadow to remove burrow sites for a non-native bee or mammal.

Bioremediation – the use of native organisms to displace and eradicate non-native organisms or to replace non-native organisms as they are eliminated from an ecosystem. This is an expansion of the traditional definition of bioremediation. Whereas, traditional bioremediation is the use of microorganisms or plants to mitigate chemical or organic pollution. This is the use of the term to mean use of native organisms to restore an ecosystem during the process of and after the removal of a non-native organism or non-native organism system.

Mutualism – Two or more organisms which cooperate to the benefit of each other. Bioeradicant systems reflect this at different levels of relationship by eliminating a non-native from the ecosystem through (unintended) cooperation, different feeding strategies which enhance the success of both species, behavioral adaptations or other strategies.

Competition – Relationships where certain organisms benefit through a variety of mechanisms to the detriment of others without necessarily using them as an energy source. This is an essential element in bioeradication.

Enemy Release Hypothesis (ERH) - It is the disease/pest/competitor version of the Founder Effect but exchanges genes for the biological controls. This frees the plant to focus on growth and reproduction. In essence it is a pest bottleneck effect for reducing the hindrances which a non-native has in its native ecosystem.

The final effect is the elimination of many of the restraints which prevented the non-native organism from taking over its home ecosystem.

Evolution of Increased Competitive Ability (EICA) – the evolution of a non-native organism to a new ecosystem by ridding itself of genes and genotypes which are unsuitable in the introduced ecosystem and developing new genes or genetic synergies that increase its ability to adapt and survive. It is mostly seen on the front end of the sigmoidal curve of adaption, exponential population growth and plateauing that is found during the introduction of most invasive non-native organisms into a new ecosystem.

Biocontrol target selection concerns involving propagule spread

Propagule spread is an important component of how problems develop. With Mile-a-minute, it is obvious that migrating birds spread the seeds first locally then along the species specific migration corridors. As more species develop a taste for the berries, they will too spread the seeds along their migration corridors, … .

In a similar way, the seeds of the various honeysuckles and Multiflora rose are spread primarily by birds, such as mocking birds in the case of multifora rose. In both of these examples native or native/non-native hybrid systems are forming to eradicate the non-native invasive plants. This is the only way possible to eradicate these plants.

In contrast, the seeds of the various species of grapehyacinth, (Muscari sp.) and periwinkle (Vinca sp.) spread through a slow and localized process which deposits most of the seeds within a foot or clone sequentially from a parent plant . If a migratory bird or mammal develops a taste for the seeds or vegetatively reproductive parts, this will become a major problem the same as with the aforementioned species. However, with infestations such as these, minimal intervention will be successful.

In between these examples are plants such as Japanese stilt grass and garlic mustard which depend on animals, including humans, to spread their hitchhiking seeds.

Unfortunately, humans are very efficient at spreading hitchhiking seeds long distances.

Concepts demonstrated graphically

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Non-native biocontrol

Non-native invasive

Native congeners and conspecifics of non-native invader

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Simplified expected curves for what happens when a non-native biocontrol is introduced after the establishment of a non-native invasive due to the

biocontrol adapting to new food sources without defenses to that biocontrol.

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Native bioeradicant

Non-native invasive

Native congeners of non-native invader

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The expected population curves for native bioeradicant use. The baseline population for native organisms changes as the native bioeradicants adapt to the non-native invasive and eat a few more of the native while the system comes back into balance as the non-native is destroyed.

There is some recoverable risk to the native ecosystem, but not the unrecoverable risk of introducing non-native biocontrols.

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Non-native biocontrols

Pioneer non-native invasive

Native congeners of non-native invasive

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Secondary non-native invasives

A more complex version of what happens when a (pioneer) non-native plant is introduced followed by its non-native biocontrol. The native system collapses allowing secondary non-

natives to enter.

Native organisms

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Non-native specialist biocontrol

Non-native invasive Chemical defenses of non-native invasive population

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This diagram demonstrates what happens when a non-native specialist biocontrol is reintroduced to its non-native host.

More on Ailanthus altissima

From recent walking it appears that there is a correlation between the density and nearness of the nectar sources adult Atteva aurea feed on

and the amount of disease in a stand of Ailanthus.

The key to finding a native biocontrol (system) for a plant is to find an organism which is a generalist

herbivore for a family or genus and a specialist to that family or genus.

This means that the bioeradicant has the genetic ability to switch from one

plant to another and yet will not cause the extinction of coevolved food

sources.

A. aurea larvae eat other Simbouracae family members, but only eats

members of this family.

A. aurea larvae will preferentially eat a non-coevolved food source because the food source does not have the

defenses to A. aurea that a coevolved food source has.

Hence, an easy meal that is a higher quality food source (higher energy return for energy expended) than a

native coevolved one since it spends less energy dealing with chemical and

physical defenses.

At the same time it is embedded in a system of a mite (A. ailanthii) and

several diseases.

Which together interact to cause eradication of A. altissima.

Unique features of this system: 1. A. altissima is the only food for A. aurea larvae in most of the A.

altissima range 2. A. aurea adults are broadly generalist nectar feeders

3. A. ailanthii is an apparent specialist to A. altissima 4. A. aurea larvae have no other local food sources. The adults have

spread themselves beyond their normal range by following nectar sources and egg laying sites.

5. A. aurea and A. ailanthii are the vectors for several A. altissima diseases

6. A. ailanthii apparently hitchhikes between A. altissima trees on birds and A. aurea.

7. A. aurea appears to evolving to colder temperatures as witnessed by their presence feeding on goldenrod in central Pennsylvania in

mid-November after frost and freeze.

How to develop an Ailanthus biocontrol system:

1.) Do not apply pesticides to the surrounding area – herbicides,

insecticides, fungicides, … .

2. Plant a wide variety of native high nectar flowers nearby so there are

high quality food sources from mid-spring to first heavy freeze for the

adults to feed on.

So far I have found adult Atteva aurea on daisy-like flowers and at least 2

species of goldenrod from August to mid-November. I am still not sure

what they feed on from early spring when the Ailanthus leaves are just

beginning to bloom to mid-August but expect it to be other flowers with

compact inflorescences.