Lemon-Yellow-Lepiota Leucocoprinus birnbaumii

The Yellow parasol is a gilled mushroom in a family of fungi and common to the tropics. It is easily recognized by its small size and bright lemon yellow oval or bell-shaped cap that fades to a white color with age. The Yellow parasol can reach a mature height of 1 to 3 inches and, while typically found growing outdoors in clusters in its native, tropical environment, they commonly occur in potted plants, greenhouses, and compost piles where conditions are more temerate. 

The Yelow parasol works to break down organic matter found in soils and they do not harm living plants. However, they are toxic and you should remove these mushrooms as soon as they appear if pets or small children have access to the area. Keep in mind that this species can spread by means of potting soil and transplanted plants.

Overwatering of potted plants can cause them to appear and they are difficult to manage once established. Fungicide applications are generally ineffective against mushrooms. 

Quick ID:

• CAP: Small, 1 to 2 inches in diameter, bell-shaped, fragile, margin striate, bright yellow, and covered with powder.
• GILLS: Free from stalk, yellowish white.
• STALK: Slender, slightly enlarged at the base, covered with bright yellow powder.
• ANNULUS (ring): Bright yellow, covered with yellow powder, moveable up and down the stalk, often breaking loose.
• SPORE PRINT: White, spores ellipsoidal, smooth.