The North American Species of Pholiota

100. Pholiota terrestris Overholts, North Amer. Fl. 10: 278. 1924.

Illustrations: Text figs. 199-201; pl. 44.

Pileus (1) 2-8 (10) cm broad, when young obtusely conic to convex, soon obtusely umbonate, at maturity expanded and with a slight umbo, at times nearly plane, usually covered with numerous fibrillose scales, or toward the margin merely fibrillose streaked, a gelatinous layer present beneath the scales and the latter consequently becoming rather readily weathered away, scales or fibrils "wood brown" along the margin, near "Verona brown" on the disc, when young the whole pileus evenly "warm sepia" because of the fibrillose covering, at times "Prout's brown" to "cinnamon-brown" when freshly matured, margin usually fibrillose-appendiculate. Context rather thick (more or less 4 mm), watery buff to brown, pliant and subcartilaginous; odor and taste mild.

Lamellae adnate, narrow, crowded, pallid becoming pale avellaneous and finally sometimes faintly tinged "Isabella color," pale cinnamon when dried, edges slightly uneven.

Stipe 3-8 (10) cm long, (2) 5-10 mm thick, equal or narrowed below, solid but soon hollowed, flesh grayish but with a strong tendency to stain yellow to brownish at base or around worm holes, occasionally staining where bruised or handled, surface covered to a superior annular zone or ring by dark avellaneous recurved scales, scales larger and more numerous upward, sheath at times merely becoming broken into zones or patches instead of scales, apical region fibrillose pruinose.

Spores 4.5-6.5 (7) x 3.5-4.5 µ, smooth, apical pore distinct but small, shape elliptic to broadly elliptic in face view, in profile subelliptic to slightly bean-shaped; in KOH dingy cinnamon, in Melzer's reagent paler; wall rather thin (-0.25 µ, estimated).

Basidia (20) 22-30 x 5-6.5 µ, 2- or 4-spored (mostly 4-spored), hyaline in KOH and only slightly yellowish in Melzer's reagent. Pleurocystidia 18-34 x (4) 5-10 (12) µ, clavate, clavate-mucronate, to fusoid ventricose, with the typical amorphous refractive inclusion of chrysocystidia, rarely with brown content, abundant but mostly scarcely projecting. Cheilocystidia 26-50 x 4-8 µ, numerous, cylindric, cylindric-subcapitate, sub-utriform to fusoid-ventricose, thin-walled, smooth, content homogeneous, hyaline in KOH. Caulocystidia (23) 47-88 x (94) 6-10 µ, cylindric-clavate, ventricose-capitate, to ventricose-rostrate, walls smooth, thin, yellowish in KOH.

Gill trama a central area of subparallel hyphae with hyphal cells 5-12 µ broad, walls thin, smooth, hyaline in KOH, in Melzer's reagent yellowish; subhymenium a well developed layer of narrow gelatinous interwoven hyphae. Pileus cutis with an epicutis of non-gelatinous brown hyphae with encrusted walls, the cells inflated to 12 µ at times, (these appearing to be in fascicles originating as a trichodermium, beneath this is an interwoven layer of gelatinizing brown incrusted hyphae (subcutis); hypodermium of compactly arranged mostly smooth dingy hyaline to brownish hyphae of variable diameter. Context hyphae interwoven, and with inflated cells smooth and thin-walled. Clamp connections present. All hyphae inamyloid.

Habit, Habitat, and Distribution: Caespitose on soil, roadsides, lawns, woods, more rarely on buried wood or even stumps, Michigan, Wisconsin, Idaho, Washington, Oregon, and California, June-January.

Observations: This is a characteristic road-side species in the Pacific Northwest, and most of the time appears to be terrestrial. However, we have collections from buried wood and from wood above ground. Mr. Bill Isaacs has found it lignicolous in Washington also. Hence the name is a bit deceiving. It is very close to P. squarrosoides in all features except color and habitat. Both have at first an essentially dry scaly pileus from the scaly outer layer. The chrysocystidia may often resemble basidioles in shape, but as revived in KOH have the characteristic inclusion.

We have found it in large clusters with small pilei, large clusters with large pilei, small clusters with large pilei, and small pilei in small clusters, and hence cannot assume that the amount of available food material regularly determines the size of the basidiocarp as much, possibly, as it does the size of the cluster.

We have two collections from Cusick, Wash. Smith 73375 and 74152 (the latter collected by K. Harrison) which came up on dried mud in an old logging road. The caps were 1-3 cm broad, at first covered by woodbrown scales but as these become separated the dingy yellow ground color became evident and the older pilei are dingy yellowish as dried. Yellow tints also show in the stipes of both collections. Pending further collections of this depauperate "form" we merely mention its existence here and regard it as a dry weather variant.

Material Examined: CALIFORNIA: Smith 3639, 3642, 8194, 56153; Thiers 8806; IDAHO: Trueblood 540c (MICH); Slipp 41FP 1969; Smith 569, 44149, 54030, 54489, 54814, 58500, 70478; MICHIGAN: Smith 34098; OREGON: Gruber 1946; La-1027 (MICH); Sipe 227, 232, 387; Smith 19347, 24677, 2852, 3604, 7861, 19359, 28120, 55354; WISCONSIN, Harper. WASHINGTON: E. Schmidt 2; Smith 16958, 17035, 39849, 68799; CANADA (BRITISH COLUMBIA): Waugh (Myc. Herb. Sci. Service 23958).