How to identify Oak Milkcap

To correctly identify Oak Milkcap (Lactarius quietus), 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 typically 4-10 cm in diameter, convex to plano-convex, becoming depressed in the center with age. The color ranges from dull reddish-brown to cinnamon-brown, often with faint concentric zones (zonate) or spots, especially when young. The surface is dry and smooth, sometimes slightly velvety when young.

2. 2

   Gills

   Attachment to stem, color, and spacing.

   The gills are adnate to slightly decurrent, crowded, and rather narrow. They are initially pale cream to yellowish-buff, becoming ochraceous with age, sometimes with reddish-brown spots.

3. 3

   Stem

   Length, shape, surface, and any ring.

   The stem is 3-8 cm long and 1-2 cm thick, cylindrical or slightly tapering towards the base. It is concolorous with the cap or slightly paler, often with a pruinose (powdery) surface, especially when young. It is solid when young, becoming hollow with age.

4. 4

   Flesh

   Color, texture, and bruising reaction.

   The flesh is firm, whitish to pale brownish, and does not change color when cut. It exudes a white to watery-white latex that is mild to slightly acrid in taste and does not change color.

5. 5

   Fruiting body

   Overall growth pattern.

   The fruiting body is a typical agaric (gilled mushroom) with a cap, gills, and a central stem. It exudes a milky latex when cut or bruised.

6. 6

   Habitat

   Where it grows and on what substrate.

   Lactarius quietus is exclusively mycorrhizal with oak trees (Quercus species). It is found growing on the ground, often scattered or in groups, in deciduous woodlands, parks, and gardens where oaks are present.

Key Facts

Cap surfaces

Dry, smooth, sometimes faintly zonate.

Growth Form

Scattered or gregarious.

Spore Print

Cream to pale ochre.

Body color

Reddish-brown to cinnamon-brown cap, paler stem.

Odor

Faint, sometimes 'buggy' or 'geranium-like'.

Flesh bruises

Does not bruise significantly; latex is unchanging white/watery-white.

Height

3-8 cm

Cap Diameter

4-10 cm

Fruit body characteristics

• Gill attachment: Adnate to slightly decurrent.
• Stem shape: Cylindrical or slightly tapering towards the base.
• Stem surface: Smooth, sometimes pruinose.
• Ring: Absent.
• Stem cross-section: Solid when young, becoming hollow with age.

Explore Oak Milkcap