About Amanita calyptroderma G.F.Atk. & V.G.Ballen
The cap of Amanita calyptroderma G.F.Atk. & V.G.Ballen ranges from 10 to 25 centimetres (4 to 10 inches) in diameter, and is most often orange-brown, though occasionally it appears white. The cap is partially covered by a thick white patch of universal veil. This species has white, closely spaced gills. Its cream-colored stalk measures 10 to 20 cm long and 2 to 4 cm (3⁄4 to 1+1⁄2 inches) wide, and features a partial veil. The stem is partially hollow, with a filling of stringy white pith, and has a large, sacklike volva at the base of the stalk. The spores of Amanita calyptroderma are white, and do not change color when exposed to Melzer's reagent, a trait called inamyloid. This inamyloid spore characteristic, along with the presence of a skirt-like annulus and the absence of a bulb at the stalk base, places this mushroom in section Caesareae. This mushroom grows in conifer forests and forms mycorrhizae. In the southern part of its range, from Central California north to Washington, its mycorrhizal partner is madrone (Arbutus menziesii). In the northern part of its range, from Washington to southern Canada, its preferred mycorrhizal host is Douglas-fir (Pseudotsuga menziesii).
