Fruiting body 2.0-5.0 cm tall, 2.0-3.5 cm broad, subglobose to pear-shaped, with or without a well developed pseudostipe, at maturity opening via an apical pore; exoperidium, a covering of brown to blackish-brown spines >1 mm in length, typically joined at the tips, the area between the spines covered with a thin tan-colored tomentum; endoperidium papery, buff to pale-tan, in age reticulate from scars left by the deciduous spines; gleba whitish, soon olivaceous, medium-brown at maturity; subgleba alveolate, olivaceous-brown, sometimes with lilac tints; odor and taste not determined..
Spores 4.0-4.5 µ, globose, weakly warted, moderately thick-walled, with a stub-like pedicel; spores olive-brown in deposit; capillitium Lycoperdon type, elastic, slender, straight to slightly wavy, with occasional Y-shaped branches; capillitial walls, 3.5-4.5 u in width with numerous round to elongate pores; paracapillitium present.
Solitary or in small groups in conifer woods, occasionally with hardwoods; fruiting from late fall to mid-winter; rare to occasional.
Lycoperdon nigrescens (=L. foetidum) is found primarily in the Pacific Northwest. Herbarium records are lacking, but it is reasonable to assume that it also occurs in far northern California. Lycoperdon nigrescens is often confused with Lycoperdon umbrinum, a dark puffball found regularly in the coastal forests of central California. Despite the similarity in color, the two species are relatively easy to distinguish. Lycoperdon nigrescens has spines that are >1 mm in length, typically joined at the tips which when shed, leave a reticulate pattern on the underlying buff-colored endoperidium, while Lycoperdon umbrinum has shorter spines, < 1 mm in length, with an often yellowish endoperidum that does not become reticulate in age. See Comments under Lycoperdon umbrinum for additional information.