Fly Agarics grow from the bottom near both conifers and broadleaved trees and should be frequent and widespread within the late summer and autumn. These are rather large and stout Amanitas, the cap is usually more extensive than the stem is long. They occur during a sort of color form with almost white through yellow to orange to very red or maybe brown caps. The variability described here is typical for the red-capped material found most frequently in Canada BC. They create white spore prints.
Caps 5 to twenty (25) cm wide, beginning as a hemispheric bump on top of the massive developing 'button' but soon expanding to globular in shape and expanding further to be domed or convex to flattened or uplifted in age. Cap margin is striate when young becoming actively so in maturity, these striations being grooves like the gills separated by a raised ridge often with beautiful bumps, called tuberculate striate. Cap has scattered to dense warts or scales of slightly yellowish, cream, or whitish veil material that is often very pyramidal or described as "cottage cheese." These warts are often densely distributed over the center and more scattered toward the cap edge and should be wiped or washed away. The flesh of the cap immediately beneath the surface is red, then orange to yellow lower than white. Tissue doesn't stain when cut or bruised.
Gills are white and crowded and free from the stem. Partial gills are many and truncate. The sides of the gills often have a powdery or granular fringe.
Stems are 5 to 18 cm tall, and 1 to three cm wide and are upward tapered, white, with an expanded or bulbous base. There's usually an outsized well-developed skirt-like hanging ring or annulus on the upper stem which is smooth on the top and sometimes features a thick cream to the yellowish edge. The volva is packed and leaves more or less diagonally arranged broken bands and ridges of loose cottony white to yellowish-cream material adhering to the lower stem.
Microscopic: Spores are 9 x 6 microns, smooth, thin-walled, and hyaline, broadly elliptic to elongate, non-amyloid (not blue in Melzer's iodine solution).
The Amanita muscaria is among the first conspicuous and showy mushrooms and is familiar to most people because of the classic toadstool. It's intentionally ingested by some people seeking the inebriating effects, but unlike ingestions of the Panther Mushroom, these people rarely come to medical attention. This is often because Fly Agarics contain lower and more consistent quantities of the isoxazole neurotoxins leading to milder and more predictable effects. It should be noted that while quite a few people have experimented with eating Fly Agarics and Panther Mushrooms, only a few people prefer to use them repeatedly.
There are several color forms found in Amanita that were previously formally recognized as named varieties:
Whitish caps with tan-brown warts and white stem turning yellowy-orange where handled characterized the variability alba, which is common in eastern North Canada.
Yellow to yellow-orange caps with yellowish to straw tan warts and white stem surface becoming yellowish where handled were considered as belonging to the variability Formosa. These are common within the west, especially under Poplar trees and in interior pine woods.
Orange-red or vivid red caps with distinctly yellow warts and yellowish vulval remnants and white stem surface turning tannish where handled are recognized as variety Amanita.
Brown caps indicate the rare sort of fly agaric called the variability regalis. Though this mushroom resembles the Panther Mushroom, the volva at the basal bulb may be a series of more or less diagonal loose cottony yellowish-white bands ascending how up the stem, instead of an abrupt single white-collar or rim (see Amanita Pantheria).
Molecular data, unfortunately, doesn't support this neat classification by color characteristics. There appears to be a minimum of three different lineages or clades or genotypes within our western North Canada Fly Agarics consistent with molecular studies. Still, these don't correlate to color forms or the named varieties.