A native truffle of the Pacific Northwest, prized by chefs for its rich aromatic flavor. Forms mycorrhizal partnerships with Douglas-fir roots.

Also called: Oregon White Truffle, Pacific Northwest Truffle

Native status: Native to Pacific Northwest old-growth Douglas-fir forests

§ Quick facts

SizeFruiting body 1–6 cm diameter
Weight10–100 g per truffle
LifespanUnderground fruiting bodies 1–3 months; mycelial network long-lived
OrderPezizales
FamilyTuberaceae

§ Encyclopedia

Tuber gibbosum, commonly known as the Oregon white truffle, is a species of truffle in the genus Tuber. It is found in the Pacific Northwest region of the United States, where it often grows with Douglas-fir.

Source: Wikipedia — Tuber gibbosum Licensed under CC BY-SA 4.0

§ Identification

Field marks. Small round whitish-to-pale-tan truffle; smooth or slightly warty surface; marbled white internal flesh; subterranean (no visible above-ground structure).

Similar species. Other Tuber truffle species (different ranges or hosts). European Black Truffle (different range; much rarer). Native truffles often require microscopic examination for ID.

Voice. N/A

§ Diet & behavior

Diet. Mycorrhizal — forms exchange relationships exclusively with Douglas-fir roots.

Behavior. Native Pacific Northwest truffle species, harvested commercially in Oregon. Underground fruiting bodies disperse spores only when uncovered and eaten by small mammals (especially Northern Flying Squirrels, voles, and chipmunks), which excrete intact spores in their droppings — a mutualism critical to Douglas-fir forest health since the mycorrhizal fungi extract phosphorus and water that the trees cannot reach. Aroma compounds attract truffle dogs (specially trained dogs that find truffles by scent).

§ Range

Pacific Northwest

§ Habitat

Under Douglas-fir roots

§ Threats

Conifer forest loss, soil compaction from logging, climate change.

§ Conservation status

According to the IUCN Red List, the western truffle (tuber gibbosum) is currently classified as Least Concern.

§ What helps

Support old-growth Douglas-fir forests. Buy ethically sourced truffles. Don't dig up mycelial mats.

Support our work More ways to help

§ Further reading

§ Sources cited

  • North American Truffling Society
  • Oregon State University Pacific Northwest Mycology Lab
  • USDA Forest Service