Denver Botanic Gardens reports that Colorado has a state mushroom as of February 2025. The official species is Agaricus julius, a saprotrophic mushroom that feeds on dead plant material such as leaf litter, sticks and woody debris. It grows in the southern Rocky Mountains under spruce and is distinguished by its large size, brown cap scales and almond odor.

Initial discussion about naming a state mushroom began around 2021. Alex Merryman, a volunteer at Denver Botanic Gardens and a member of the Colorado Mycological Society, led the effort. Former CMS president Greg Sanchez then began working with his Horizon High School civics class in Thornton, Colorado, on discussing the process for introducing a state mushroom. In the latter half of 2024, it was decided that Agaricus julius would be the species proposed to the Colorado General Assembly.

After testimonies on Feb. 3, 2025 by a group of mycology enthusiasts, including the Gardens’ Andrew Wilson and Horizon High School students, the bill was approved by the House committee.

Colorado Mycological Society handle: @colomycosociety.