About Agaricus crocodilinus Murrill
This mushroom species, Agaricus crocodilinus Murrill, has a cap that starts round before becoming broadly convex. Young caps measure 5–12 centimetres (2–4+1⁄2 inches) across, while mature caps can reach 20–40 cm (8–15+1⁄2 inches) in width. Its stipe is 6–20 cm (2+1⁄4–7+3⁄4 inches) long, 2–4 cm (3⁄4–1+1⁄2 inches) wide, and bears a ring. The gills are free from attachment to the stipe; they start out tannish, and later become reddish to blackish brown. Agaricus crocodilinus is saprophytic, and most often grows in heavily grassed prairies and pastures. It is considered edible and highly regarded, but it frequently contains maggots even when young, and can be confused with at least one poisonous species. It is also known to accumulate the toxic chemical cadmium, even when growing in non-polluted areas.