Described as new to science in 2010, the North American species is found on the western coast of the United States, from northern California to southern British Columbia west of the Cascade Range.

The fruit bodies of the fungus are roughly spherical to irregular in shape, and resemble small potatoes up to 5 cm (2 in) in diameter.

The peridium is 0.2–0.4 mm thick, and the surface texture ranges from relatively smooth to covered with tiny "hairs" that are more dense in the furrows, and more scattered on the exposed lobes.

The gleba is solid; in youth the fertile tissue is whitish and marbled with mostly narrow, white, hypha-stuffed veins that emerge throughout the peridium to its surface.

Young asci range in shape from spherical to broadly ellipsoid to ovoid (egg-shaped) or pyriform (pear-shaped); sometimes the base of the ascus is narrowed like a stipe, and measures up to 15 by 7 μm.

The degree to which the surface is covered with fine "hairs" is variable; these hairs are made of tangled hyphae and emergent thin-walled hyphal tips 2–5 μm in diameter, some even and smooth, some with granulated surfaces and some with moniliform walls (resembling a string of beads) that are irregularly thickened by hyaline bands that are 0.5–2 μm wide.

[1] Tuber oregonense closely resembles T. gibbosum, which grows in the same habitats, but may be distinguished by the structure of its peridium, and differences in spores size and shape.

[9] Its odor has been described as "truffly", a complex of garlic, spices, cheese, and "indefinable other essences"; the fungus is prized by commercial truffle harvesters and consumers for its intense fragrance.

[2] Because they grow in the topsoil and needles, they are considered to have a more "floral" and "herbal" flavor profile than related European truffles.

The fungus grows west of the Cascade Mountains from the southern Puget Sound region of Washington, south to southwestern Oregon at elevations from near sea level up to 425 m (1,390 ft) in pure stands of Pseudotsuga menziesii forests up to 100 years old, or Pseudotsuga mixed with Tsuga heterophylla, Picea sitchensis, or Alnus species.