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INS IDE
ushrooms, conks, and truffles arethe fruits of fungi, much as applesare to apple trees. Many of us
enjoy fleshy mushrooms as vegetables inour diets even though they are closer tomeat in nutrition. Cultivated mushroomscan be purchased in the grocery store orwild ones can be found in many woodlandand field environments. Mushrooms growabove the ground’s surface and come inmany shapes or sizes—and, of course, notall are edible!
Fungi are complex organisms. Theirbodies actually consist of a network (calleda mycelium) of thread-like filaments (calledhyphae) that live in soil, decaying organicmatter, or insect and animal tissue. Fungican be either beneficial or detrimental toplant growth. Some fungi cause diseasesthat can harm or kill plants. For instance,many fungi that rot tree stems fruit asconks instead of mushrooms. Conks are the
tough towoodyshelf-likestructuresseen onthe trunksof infectedtrees.Root dis-eases,commonlyfound inmany for-est areas,are anoth-er exampleof harmfulfungi.
Most fungi in our forest, however, arebeneficial. When fungi that are called“mycorrhizal” (literally “fungus-root”) growin association with plant roots, both theplant and fungus derive benefits. The fun-gus improves the ability of the plant toextract needed water and nutrients from thesoil. At the same time, the plants providethe fungi with carbohydrates that they pro-duce through photosynthesis. This mutual-ly beneficial or symbiotic relationshipbetween the fungus and a plant is essentialfor both organisms to survive and flourish.All the trees and almost all plants inOregon’s forests depend on such fungi fortheir very existence, let alone healthygrowth.
Oregon Truffles...a Culinary Delightfrom the Forest
Page 2Truffles...
Page 2Truffles areImportant to theForest
Page 2Really GreatTruffles!
Page 3Truffles areImportant toPeople
Page 3Oregon’s Trufflesand their Collection
Back pageWhere Oregon’sTruffles Grow
Back pageMore Information
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The Pacific golden chanterelle, one ofOregon’s gourmet wild mushrooms,is a common inhabitant of our west-ern Cascade and Coastal forests.
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This closeup photo shows the fine, hair-like hyphaeof beneficial mycorrhizal fungi growing from thetips of a tree root.
A Practical Guide to Forestry from the Oregon Garden Rediscovery Forest and the Oregon Forest Resources Institute
TrufflesAn Oregon Garden guide to
uring the past 30 years,much has been learned aboutthe connections between for-
est plants, animals and fungi. Forinstance, in old growth forests, thetrees, spotted owls, flying squirrels,and truffles are all interdependent.The species of mycorrhizal fungithat produce truffles when they fruitalso act as the fine root system fortrees. In return, the truffles obtaincarbohydrates from the trees thatthey cannot produce themselves.
Flying squirrels that live in theseolder forests glide down at night toforage on the ground for food.Truffles, a primary part of their diet,are dug up and eaten with relish.Truffles depend on the flying squir-rels, too. When the squirrels defecateelsewhere, they spread the spores ofthe truffles to new locations. In thisway, tree seedlings have little packetsof spores from beneficial fungideposited near their roots.
Finally, the northern spotted owlfeeds on flying squirrels. The owls,
then, also deposit packets of squir-rel- and spore-remains even furtheraway, benefiting trees elsewhere. Inturn, the older forest habitat pro-vides shelter and food for the spot-ted owls and squirrels. Oregonforests have literally hundreds offungal species that produce trufflesand the animals that feed on themalso are varied. Such complex,interlinked food webs are more therule than the exception.
Truffles are Important to the Forest
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ruffles also are the fruitingbodies of mycorrhizal fungithat live in soil and associate
with tree roots. But, instead offruiting above ground, the trufflefruits below ground—and neversees the light of day (unless it is dugup). As a result, most people havenever seen a truffle! Yet, truffles arecommon in the PacificNorthwest—especially in ourDouglas-fir forests.
Generally, truffles are round,somewhat bumpy, or irregularly-shaped structures that vary in theirmature size from a pinto bean to aman’s fist. All fungal fruiting-bod-ies (mushrooms, conks, and truffles)produce spores (equivalent to smallseeds) to reproduce. Because mush-rooms and conks fruit aboveground, wind can move their sporesaround.
Truffles need another method.Almost all truffles are very odiferouswhen they mature. Mammals suchas rodents, deer, bear, elk, raccoons,and pigs actively seek truffles andeat them. The spores pass throughtheir digestive tracks unharmed andget deposited elsewhere. Thismeans of reproduction has impor-tant implications for both forestsand people.
Truffles
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Mature-sized Oregon truffles.
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Flying squirrels commonly feed on trufflesin our older western Oregon forests.
Really Great Truffles!
Although found in several regions of the world, the most famous areas fortruffle production, gathering, and use are in France, Spain, and Italy. TheFrench Black Truffle and the Italian White Truffle have long been consid-ered an essential ingredient in fine cooking in Europe. As far back as theGreeks and Romans, truffles have been used for cooking, as an aphrodisiac,and medicinally. As a result, truffles are among the world’s most expensivenatural foods. Top quality Italian white truffles routinely sell for up to$2,000 per pound. In a 2005 auction in Italy, a 2.4 pound truffle (one ofthe biggest ever found) sold for $52,000, the highest price ever paid!
Only in the past 20 years or so have several species of Oregon trufflesbecome recognized for their culinary quality and potential value in the mar-ketplace. In fact, with truffle production declining in Europe since 1900,Oregon’s relatively untapped supply is gaining more and more notice.None-the-less, Oregon truffles generally command a much lower price intoday’s marketplace, compared with their European counterparts. Oregontruffle prices vary widely but can range from $50-500 per pound. The typeof truffle, its ripeness, and current market demand all affect the price.
umans can’t smell as well asmost wild animals, and per-haps that is fortunate. All
truffles have strong odors, and manyare disagreeable to humans. But afew species of truffles around theworld cause some people drool.Why this allure? It’s all in the par-ticular odor of a few types of truf-fles. Grated over a dish of food, atiny amount of truffle shavings canchange a common dish into food forroyalty. The ripeness or maturity ofthe truffle is the key, because theodor only becomes intense when the
spores are ready to be released.Gourmet chefs describe culinary
truffles as smelling earthy, musky,pungent, or nutty, or similar to garlicor blue cheese, although none ofthese adequately describe the odors.Truffles don’t really have much of a“taste”, but the smell is so overwhelm-ing that it infuses any meal (and oftenthe refrigerator). To the non-aficiona-do, the truffle’s smell is likely to beone that has to “grow on you.”
There are many wonderful recipesfor using truffles in cooking andfood preparation. The truffle’s
aroma and flavor can be destroyedby heat, so finding ways to incorpo-rate their use into food preparationwith little or no heat is important.The truffle odor molecules also clingto fat molecules. As a result, one ofthe classic recipes is a truffle butter,where fresh grated truffles are addedto a softened butter for flavoring.Anything from eggs to roast turkeyscan be flavored with truffles.
Not only do truffles need to beripe to develop the strongest odors,but they need to be fresh. Properhandling, quick shipment, andprompt use preserve these qualitiesand enhance the dinning pleasure.
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wo main types of Oregontruffles are currently harvest-ed in the state, the Oregon
white truffles (Tuber oregonense andTuber gibbosum) and the Oregonblack truffle (Leucangium carthu-sianum). The white truffles areactually two species that fruit at dif-ferent times of the year, but are soldas the same truffle.
So how does one find an under-ground truffle? Female pigs wereoriginally usedto seek themout in Europebecause theodor of culi-nary trufflesresembled amale pig’s sexattractantpheromone.Unfortunately,pigs love to eattruffles and itis not easy toreign in a largesow. Dogs canbe trained tohunt truffles,
too, and are content with othersnacks as a reward, so they are com-monly used to find ripe truffles inEurope now.
In Oregon, much truffle collec-tion is still done by random rakingof the forest floor. This is unfortu-nate because immature truffles arealso uncovered and sold, and theirlack of odor diminishes the reputa-tion of Oregon truffles. If Oregon’struffle industry is to reach its full
potential, truffle hunters need to usetrained dogs and chefs mustdemand only ripe truffles.Moreover, raking for truffles isunsightly and might spread treeroot diseases on the tines of therakes.
Oregon’s Truffles and their Collection
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Oregon black truffles (larger two on left) and Oregon white truffles(smaller four on right). The white truffle slices on bottom are ripe, theones above are not yet. The black truffle is not quite ripe, becoming alittle darker inside at maturity.
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Trained dogs are considered ideal trufflehunters.
Truffles are Important to People
ruffles growfromVancouver
Island, BritishColumbia, south tonorthern California.Fortunately forOregonians, primehabitat for Oregon’sculinary truffles(both white andblack) is found inyoung, fast-growingDouglas-fir treeplantations in thefoothills of theWillamette Valley.Even Christmas tree plantations nearthe age of harvesting will produceOregon truffles. Such “truffle-plan-tations” can yield annual crops oftruffles that far exceed the value ofthe trees (although both can becropped in rotation).
Not only are such forests andplantations abundant, privately-owned, and easily accessed, but truf-fle patches might be easy to estab-lish (if they are not already there).Some truffle harvesters andlandowners claim that new trufflepatches can be established by grind-ing mature truffles and spreadingthem (and thus their spores) in awater slurry. This claim has yet tobe verified using scientific methods,but knowing if this is true would
benefit the young Oregon truffleindustry. Either the method couldbe used more widely or avoided as awaste of time.
Preventing trespass and unautho-rized harvesting can be a concernfor landowners who wish to get themost value from their truffle crops.If the landowner does not wish toharvest truffles themselves, makingarrangements to provide exclusiveaccess to trusted harvesters inexchange for a portion of the salesprice is good approach. Oregon’struffle industry still needs someimproved methods of harvestingand marketing, but the potentialeconomic returns to the state and itscitizens are large. To say nothing ofthe fortunate diners!
Where Oregon’s Truffles Grow
Thousands of acres of fast-growing Douglas-fir plantations havebeen established in the Willamette Valley and surroundingfoothills during the past 30 years. These plantings now provideexcellent habitat for Oregon’s truffles.
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879 West Main StreetSilverton, OR 97381
503-874-8265Fax: 503-874-8272
Contact: Julie WoodwardE-mail: [email protected]
Visit the Oregon Garden website athttp://www.oregongarden.org
for more information or directions
Visit the Rediscovery Forestat the Oregon Garden
The Rediscovery Forest located atthe world-class Oregon Garden inSilverton provides an opportunity tolearn first-hand about Oregon’s forestresources and how they are managedto provide environmental, social andeconomic benefits.
The Rediscovery Forest offers:• K-12 school programs and activities
• Special Education events
• Service Learning andCommunity Service projects
• Teacher workshops
• Adult classes
• Workshops for family forest landowners
• Group tours
• Self-guided tours
F O R M O R E I N F O R M AT I O NNorth American Truffling SocietyPO Box 296, Corvallis, OR 97339-0296 http://www.natruffling.org
New World TruffieresP.O. Box 5802, Eugene, OR 97405http://www.truffletree.com/index.html
AuthorsDave Pilz, Forest Mycologist, Department of Forest Science, Oregon StateUniversity, Corvallis, ORMike Bondi, Oregon State University Extension Agent, Oregon City, OR