Cite as: Trappe, J. M. The hunted: commercially attractive truffles native to North America. In Les champignons forestiers comestibles à potentiel commercial. ÉDITEUR. Biopterre, ACCHF, Université Laval, CEF, RNC, 30 novembre et 1er décembre 2009. pp. 97-102 Available at http://194.254.27.242/photo/10.pdf 11/29/2012. The hunted: commercially attractive truffles native to North America James M. Trappe Department of Forest Ecosystems and Society Oregon State University Corvallis, Oregon, USA 97331-5752 INTRODUCTION A few herbarium packets of North lyonii Butters) from Texas and the American truffles have annotations yellow furrowed truffle, Tuber hinting at sale of specimens harvested by canaliculatum Gilkey, from the Italian immigrants to restaurants in New Northeastern USA and York City in the early 20th century, but pronounced both to be “exquisite” the first recorded commercial harvesting (James Beard, personal communication). began with the founding of the North The pecan truffle has entered commerce American Trufflling Society (NATS) in at least regionally in Georgia, but I am Oregon in 1978 (Rawlinson et al.1995). not aware of any commercial harvest of Members not only sought native truffles T. canaliculatum. Finally, localized with great enthusiasm but also tried all populations of the giant Imaia (Imaia species found in various culinary gigantea) have been found in the combinations with other foods. Early on, Appalachians of North Carolina and the Oregon white truffle (Tuber Tennessee, and limited commercial gibbosum Harkn.) gained a reputation as harvesting has begun (Kovacs et al. being particularly desirable. Other 2008). species also achieved positive reputations in the region: the Oregon Wild truffle harvesting in North black truffle (Leucangium carthusianum America is an unregulated endeavor, and (Tul.) Paol. and the Kalapuya brown neither all harvesters nor all chefs are truffle (Kalapuya brunnea M. Trappe, expert identifiers of truffle species. I Trappe & Bonito, formerly termed the have been asked several times to identify Oregon brown truffle under the specimens purchased by restaurants, and provisional name Leucangium brunneum on some occasions the purported Oregon nom. ined). These and the many other white truffles were none of the species but less desirable genera and species in mentioned above and generally had little the region are discussed by M. Trappe et fragrance or an unattractive one. al. (2007, 2010) and J. Trappe et al. The earliest establishment of (2009). truffières of the European black truffle (Tuber melanosporum Vittad.) in North Meanwhile, the celebrated chef, America is not documented, but the first James Beard, had opportunity to one to produce truffles appears to be that experience the pecan truffle (Tuber established in 1982 by Bill Griner and his associates near Laytonville, only infrequent inflated cells. California. Its first truffle production Both types differed from all other was in 1987 (Rigdon, 2004). Since then, known Tuber spp. by having a sparse many additional truffières have been surface pubescence of emergent hyphal established along the West Coast from tips with a beaded appearance derived British Columbia through northern from swellings scattered along the California, in Texas, Tennessee, North hyphal wall. Together, the presumed two Carolina, and probably other states of species occurred from the San Francisco the eastern seaboard. The most Bay region north to Vancouver Island, productive truffière so far documented British Columbia. DNA analysis of for North America is Tennessee Truffles, specimens from an array of geographic which produced about 90 kg of Tuber and seasonal collections then revealed a melanosporum in the 2008-2009 season complex of four closely related but well (Michaels 2010). A good review of the defined species (Bonito et al. 2010): truffle industry in Oregon by Pilz et al. Tuber gibbosum, T. bellisporum Bonito (2009) covers both native truffles and & Trappe, T. castellanoi Bonito & black truffle truffières. I have not seen Trappe, and T. oregonense Trappe, an equivalent review for other parts of Bonito & P. Rawlinson. the continent. Morphologically and seasonally they With this brief background, the rest overlap to some degree, so microscopy of this paper outlines what is known is needed to accurately identify species. about the North American truffle species All are generally equivalent in aroma currently produced in commerce or and flavor when fully mature, so they having good potential for that. need not be distinguished from one another for marketing purposes. Bonito et al. (2010) fully describe each species. THE NORTH AMERICAN Oregon white truffles are strongly COMMERCIALLY HARVESTED pungent-garlicky-spicy when mature. TRUFFLES They can be used in much the same way as the Italian white truffle (Tuber THE TUBER GIBBOSUM COMPLEX magnatum Vittad.). Numerous culinary (OREGON WHITE TRUFFLES) uses of Oregon white truffles are described by Evans and Evans (1987). Until recent decades, T. gibbosum The distributions of Oregon white was regarded as a single species truffles differ somewhat between occurring from northern California species, though all tend to be most through western Oregon (Gilkey 1954). common in western Oregon (Bonito et Numerous collections by NATS al. 2010). All occur in southwest members, however, extend the range to Washington State south to northern British Columbia and indicated that two California. T. gibbosum goes the farthest similar related species are involved. T. north to southern Vancouver Island. T. gibbosum in the strict sense was castellanoi reaches the farthest south collected mostly in winter through with an outlier collection from the spring and was termed the “spring northern Sierra Nevada mountains. T. Oregon white truffle.” It has ellipsoid to oregonense and T. bellisporum have the broadly ellipsoid spores and an outer smallest distributions, T. oregonense peridium composed of several tiers of from southern Puget Sound in inflated cells. The other, occurring Washington State to southwestern mostly in late autumn into winter, was Oregon and T. bellisporum shifted south, designated the “autumn Oregon white from far southwestern Washington into truffle” characterized as containing northern California. narrowly ellipsoid spores and an outer peridium of interwoven hyphae with Habitat-wise, all four species abound in mesic habitats bearing young full maturity becomes wine-like or plantations to small sawtimber forests of penetrating. Cooking volatilizes its fruity Douglas-fir (Pseudotsuga menziesii) at aromas, so it is best used raw in salads or relatively low elevations (≤ 600 m) west as a complement to cheeses. of the Cascade and Sierra Nevada. Oregon black truffles have been Christmas tree plantations are reported from the Willamette Valley and particularly productive producers, so the its surrounding foothills of northwestern potential of a dual, truffle-Christmas tree Oregon to coastal forests, then north crop is substantial and merits through western Washington to developmental research. In addition to southwestern British Columbia. It the most common host tree, Douglas-fir, appears to be associated with Douglas- Abies spp. in pure plantations or in fir, particularly in stands of small to forests are also recorded as occasional large poles. In habitats where they occur, hosts. Oregon black truffles can abound and reach good size, often several fruiting LEUCANGIUM CARTHUSIANUM (OREGON together in pockets. BLACK TRUFFLES) KALAPUYA BRUNNEA (OREGON BROWN It may seem strange that Leucangium TRUFFLES) carthusianum (Tul. & C. Tul.) Paol., originally described from eastern France, The newly described genus has become known in North America as Kalapuya is named for the Kalapuya the Oregon black truffle. The DNA of tribe of native Americans, because its western Oregon representatives differs range roughly coincides with the little from that of European ones (M. ancestral homeland of the Kalapuyas. It Trappe et al. 2010). The reason for this is a relatively large, brown, warty truffle huge disjunction in occurrence of a with an interior similar to that of Oregon single species has not been explained, black truffles. Originally, its but it seems to be more common in macroscopic similarity to Leucangium Pacific northwestern USA and caused it to be provisionally named southwestern Canada than in Europe. Leucangium brunneum, although its The surface of Oregon black truffles spores are ellipsoid rather than eye- is black to brownish black and shaped. roughened to warty. The interior is whitish, at maturity consisting of DNA analysis showed that it irregular, gray to olive gray, spore belongs in the Morchellaceae along with bearing pockets embedded in whitish Leucangium but merits a separate genus tissue. Its spores are distinctive, up to 90 (M. Trappe et al. 2010). Like μm long, smooth and shaped rather like Leucangium, it does not look anything a human eye. At maturity when the like a morel. M. Trappe et al. (2007) spores are seen through the microscope describe and illustrate Kalapuya (as at this stage, one gets the sensation that Leucangium brunneum). eyes in the slide mount are gazing back Kalapuya brunnea M. Trappe, at one. The Oregon black truffle is Trappe & Bonito ranges from described and illustrated by M. Trappe et northwestern California to northwestern al. (2007). The species is in the Oregon at elevations up to about 500 m. Morchellaceae as evidenced by DNA It has not been found north of the analysis (M. Trappe et al. (2010), Columbia River. although by morphology alone it is difficult to suppose a relationship to The aroma of K. brunnea is garlicky, morels. weak in early maturity and becoming stronger as it matures. It can be diced In youth, Oregon black truffles have and added raw to pasta or other dishes a fruity, pineapple-like aroma which at for flavor and texture and for making garlic butter. Elliott. It seemed to be well matured and had a nice, fruity red wine aroma. This species occurs in Douglas-fir The giant Imaia occurs in autumn stands up to about 50 yrs old in mesic amongst mosses or in the upper 10-15 habitats. cm of humus of deciduous or mixed deciduous-conifer forests.