The North American Species of Pholiota

57. Pholiota destruens (Brond.) Gillet Champ Fr. p. 442. 1876.

Agaricus destruens Brondeau, Plant Crypt. Agen. pl. 6, 1828-30.
Dryophila destruens (Brond.) Quélet, Enchir. Fung. p. 67. 1886. var. destruens

Illustrations: Text figs. 56-58; pls. 21, 22, 23.

Pileus (6) 8-16 (20) cm broad, convex when young, expanding to broadly convex, rarely umbonate, viscid, pallid to whitish, or creamy to ocher, at times gradually darkening on the disc throughout to avellaneous, wood-brown, or "Dresden brown" (dark yellow-brown), conspicuously decorated with the whitish to dingy buff remains of a copious veil in the form of floccose scales or patches which may become matted down in age or be washed off entirely, margin shaggy from the copious veil remnants. Context thick, firm, white; odor not distinctive (usually fungoid), taste slightly disagreeable but hardly distinctive.

Lamellae adnate to sinuate, broad, close, white when young but gradually becoming deep rusty cinnamon from the spores, edges even.

Stipe central to eccentric, 5-12 (18) cm long, 1-3 cm thick at apex, enlarged downward and (2) 5-7 cm thick at the base, clavate to equal, hard, solid, white at first, brownish at least below in age (especially if water-soaked), copiously decorated with the remains of the thick, white, floccose veil as scales or patches up to the floccose-cottony evanescent annulus, silky above.

Spore deposit "cinnamon-brown"; spores 7-9.5 x 4-5.5 µ, smooth, apex in some obscurely truncate from a distinct apical pore, near cinnamon brown as revived in KOH, paler in Melzer's reagent, wall appreciably thickened (up to 0.5 µ), in face view elliptic to ovate, in profile somewhat inequilateral to elliptic, apiculus not conspicuous. Basidia 28-35 x 5-7 µ, mostly 4-spored, clavate, hyaline in KOH, faintly yellow in Melzer's reagent. Pleurocystidia none. Cheilocystidia 25-34 (66) x 4-9 µ, cylindric, narrowly clavate, or cylindric-capitate, walls smooth, hyaline and thin, content homogeneous. Caulocystidia abundant, vesiculose and up to 22 µ diam; clavate and up to 18 µ, and variable in length or as chains of broadly ellipsoid cells 10-15 µ diam., all elements hyaline in KOH, thin-walled and content homogeneous.

Gill trama of parallel hyphae 4-9 µ wide but cells becoming more inflated in age, hyaline in KOH, thin-walled, smooth, in Melzer's reagent ochraceous to reddish; subhymenium of parallel to somewhat interwoven narrow (2-3 µ) subgelatinous hyphae and base of basidium subgelatinous at times. Pileus with a poorly defined cuticular zone of subgelatinous hyphae 4-7 µ diam. hyaline in KOH and thin-walled, smooth; in Melzer's yellowish; hypodermium not differentiated by color or structure but hyphae the same size as in the context (7-20 µ diam.), hyaline, thin-walled, and smooth; in Melzer's reagent yellowish to orange-reddish in places. Clamp connections present.

Habit, Habitat, and Distribution: On logs and dead wood of Populus, especially cottonwood and balsam popular late in the fall, Michigan, Colorado, Wyoming, Idaho, Utah, Oregon, Washington and New Mexico, reported by Overholts (1927) from New York through the Central States to the Pacific and also known from Canada.

Observations: This is one of the most robust and striking species in the genus. It is most unfortunate that it has so little to recommend it for the table. It is to be expected during warm wet weather in late fall, especially in the irrigated regions of our western states. Young dried basidiocarps are pallid and show copious remains of the veil along the margin. Older basidiocarps tend to dry brownish. The veil remnants disappear slowly or may finally wash away. Lange (1938) described the odor as strong and somewhat aromatic. This feature was emphasized by Fries for P. heteroclita. We have one specimen from near Santa Fe, New Mexico collected by Barrows and Isaacs on Populus in which the stipe is 11 cm long and 1 cm thick. The veil is exceptionally cottony, thick and white, in fact the pileus is white from the evenly distributed velar remains. The spores measure 7-8.5 x 4.5-5.5 µ.

The Friesian descriptions of A. destruens cover our large late-fruiting species on Populus so well that there seems little doubt of its identity. We are not so sure of P. heteroclita and P. comosa, however, in fact at present we have not recognized them in our flora.

Material Examined: COLORADO: Smith 52221. IDAHO: Smith 54193, 73484; Trueblood 704, 785. MICHIGAN: Bartelli 391; Davis 9-21 -35; Dusseau 10-26-47; Harding 427, 439; Imshaug 4633; Potter 12171; Smith 51288, 64741, 64834, 66485, 71420. MINNESOTA: Kauffman 5-10-20. NEW MEXICO: Barrows 43a, 351, 908, 2089, 2710, Aug. 1961. NEW YORK: Kauffman 7-9-21; Stewart 5-10-26. OHIO: Harding 49. OREGON: Sipe 390; Smith Dec. 1941, 55352. SOUTH DAKOTA: Brenckle 50297. UTAH: McKnight F1153. Washington: Smith 10-18-52, 48918. WYOMING: Solheim 5484, 5485, 5486, 5487. Canada-ONTARIO: Cain 30814; Kelly 1736, 1816; Smith 4643.