How to identify Orange Pinwheel

To correctly identify Orange Pinwheel (Marasmius siccus), check each of these features in order. Misidentification is the most common cause of mushroom poisoning, so cross-reference multiple sources.

Step-by-step identification

1. 1

   Cap

   Shape, color, surface texture, and diameter.

   The cap is convex to nearly flat, often with a central depression. It is typically orange to orange-yellow, fading to tan with age. The surface is dry and smooth, with radial grooves or wrinkles that resemble a pinwheel.

2. 2

   Gills

   Attachment to stem, color, and spacing.

   The gills are widely spaced, adnate to adnexed, and white to pale yellow. They may be somewhat distant and not very prominent.

3. 3

   Stem

   Length, shape, surface, and any ring.

   The stem is thin, wiry, and shiny, typically dark reddish-brown to black. It is smooth and may be slightly enlarged at the base.

4. 4

   Flesh

   Color, texture, and bruising reaction.

   The flesh is thin and pliant.

5. 5

   Fruiting body

   Overall growth pattern.

   The fruiting body is small and delicate.

6. 6

   Habitat

   Where it grows and on what substrate.

   Found on decaying leaves, twigs, and other plant debris in woods and grassy areas.

Key Facts

Cap surfaces

Dry, smooth with radial grooves.

Growth Form

Solitary or in small groups.

Spore Print

White.

Body color

Orange to orange-yellow, fading to tan.

Odor

Not distinctive.

Flesh bruises

Does not typically bruise.

Height

1-4 cm.

Cap Diameter

0.5-2 cm.

Fruit body characteristics

• Gill attachment: Adnate to adnexed.
• Stem shape: Cylindrical, wiry.
• Stem surface: Smooth, shiny.
• Ring: Absent.
• Stem cross-section: Solid.

Explore Orange Pinwheel