Peppery Milkcap

Description

The peppery milkcap is a large, white or cream mushroom with a cap 6–20 cm across, dry and smooth, funnel-shaped with age, with an inrolled margin. Underneath are very crowded, narrow, white gills that turn cream with time. The stem is short, cylindrical, white and hard. When cut, the fruiting body exudes abundant white latex with a very acrid, burning taste.

It grows from summer to autumn, most often in broadleaved forests, under beech and hazel, even in dry weather when other mushrooms are scarce. In Poland it is common.

It is most easily confused with the velvety milkcap, which has a felty-suede cap and less crowded gills, and with the milk-white brittlegill, which does not exude latex. In Poland it is regarded as inedible, so it should not be collected for eating.

Identification features

Cap

Diameter 6–20 cm; flat-convex in young specimens, funnel-shaped with age, with an inrolled margin and a depressed centre. Surface dry, smooth, matt, and may crack in dry spots. Colour white with a slight cream tinge; in older specimens damaged areas turn brownish.

Hymenophore (underside of the cap)

Gills very crowded, thin, narrow, forked, shortly decurrent on the stem. White at first, becoming cream to yellowish with age.

Stem

Height 2–9 cm, thickness 1–3 cm, cylindrical, sometimes tapering towards the base, white, smooth, hard and solid; may become partly spotted with age. No ring.

Flesh

White, yellowish with age, compact, hard and brittle. Latex produced abundantly, white, turning yellow or green on drying (descriptions differ), yellow with KOH; the taste is very acrid and burning. Do not taste the flesh or the latex.

Spore print and spores

Spore print white. Spores shortly ellipsoid to roundish, amyloid, finely warted, not forming a network; size about 4.5–9.5 × 5–8 µm (descriptions give different ranges).

Habitat and distribution

Ecology. Mycorrhizal fungus with broadleaved trees, especially beech and hazel. Fruiting bodies grow on the forest floor, singly or in scattered groups, even in dry weather. Sometimes parasitised by Hypomyces lactifluorum. The fruiting bodies are eaten by squirrels.

Distribution. Europe, north-eastern Turkey (Black Sea region), eastern and central North America; introduced to Australia and New Zealand. Common in Poland, though less so than L. vellereus; grows in various forests, more often broadleaved. It is not legally protected in Poland.

Fruiting. Summer and autumn, sometimes until early winter.

What can it be confused with?

• Lactifluus vellereus (velvety milkcap) — Larger, with a felty-suede cap, a thicker stem and less crowded gills; often confused with the peppery milkcap.
• Lactifluus glaucescens (greening milkcap) — The latex and damaged spots turn blue-green after a while.
• Russula delica (milk-white brittlegill) — Does not exude latex, has a shorter stem and gills with a blue-greenish tinge, attached to the stem.
• Lactifluus deceptivus — Less crowded gills, a firmer cap margin and less acrid latex.

Never rely on a single feature. If you are not sure — do not pick it; show the mushroom to a qualified mushroom expert.

Interesting facts

• Described by Carl Linnaeus in 1753 as Agaricus piperatus; the epithet means "peppery", from the taste of the latex.
• It is the type species of the genus Lactifluus; previously it was the type species of the genus Lactarius.
• Sometimes parasitised by Hypomyces lactifluorum, which covers the fruiting body with an orange-red crust.
• Squirrels readily eat it, and the beetle Tritoma angulata feeds on it as an adult and as a larva.