Syst. Mycol. 2: 8. 1822.
Common Name: morel
Cap 2.0-7.0 cm tall, 2.0-3.5 cm broad, conic to cylindrical-conic; surface of longitudinal sterile ridges, anastomosing cross ribs and pits, the latter typically several times longer than wide, lined with fertile tissue; color overall when young, pallid, dingy-cream, pale grey to greyish-brown becoming yellowish-brown in age, the ridges usually lighter than the pits, but sometimes dark-brown in senescent specimens; cap hollow, the margin fused to the stipe; context thin, firm, colored like the cap or lighter; odor and taste not distinctive.
Stipe 1.0-4.0 cm long, 0.5-3.0 cm thick, hollow, variable in shape: equal, enlarged at the base or ventricose; in cross section, rounded to deeply furrowed or folded; surface at first more or less glabrous, in age developing minute, appressed scales (use hand lens), color at first whitish to pale grey, becoming yellowish-brown to greyish-brown at maturity.
Spores 20-24 x 12.5-15 µm, broadly ellipsoid to ovoid, smooth, thin-walled with granular inclusions, but lacking oil vacuoles.
Solitary to clustered in bark/wood chips of fresh landscaping or in disturbed locations, e.g. near compost heaps, fire pits, dirt basements, logging roads etc; also sometimes under old fruit trees; fruiting occasionally during the summer along the coast from fog drip and sprinklers, again from late winter to spring.
Edible and choice, but see "Comments".
Prized for their culinary value and distinctive in appearance, morels (Morchella spp.) are a favorite of mushroom hunters. Distinguishing features include pitted, ridged caps, a cap margin fused to the stipe (except in Morchella semilibera), and a hollow interior. Inexperienced collectors should familiarize themselves with species in related genera: Verpa, Helvella, and Gyromitra, some with common names like False Morel, Spring Morel, and Early Morel. These pretenders can easily be avoided with a little study. It should be noted that some Gyromitra species (False Morels) contain monomethylhydrazine (MMH), a volatile toxin which in high doses can be fatal.
Despite an extensive body of literature and intense interest, the taxonomy of morels, is poorly known. Even the number of morel species is a matter of debate. Dozens have been described, but the number of "good" species may be fewer than ten. Fortunately for amateur mycologists, morel species can at least be grouped by color, either yellow or black. In coastal California, both yellow and black morels occur, the common blonde species best fitting the description for Morchella deliciosa. This morel is characterized by a generally conic cap and an overall pallid to yellowish-brown color. The pits are generally several times longer than wide, and usually darker than the ribs, just the reverse color pattern of black morels, members of the Morchella elata/M.angusticeps group. Morchella deliciosa is an excellent edible, but like most wild mushrooms should not be eaten raw. Occasional gastrointestinal upsets are reported with morels so moderation is advised when trying for the first time. Some adverse reactions may be due to the collection of old, deteriorated specimens. Morchella esculenta is similar but has a more oval-shaped cap.
The correct name for our local blonde morel is probably Morchella rufobrunnea Guzmán & F. Tapia.
Guzmán, G. & Tapia, F. (1998). The Known Morels in Mexico, a Description of a New Blushing Species, Morchella rufobrunnea, and New Data on M. guatemalensis. Mycologia 90(4): 705-714.
Medardi, G. (2006). Ascomiceti d'Italia. Centro Studi Micologici: Trento. 454 p.
Weber, N.S. (1988). A Morel Hunter's companion. Two Penninsula Press: Lansing, MI. 288 p.