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Blue indigo milk caps with blue stems in leaf litter
Ediblebeginner-friendly group

Indigo Milk Cap

Lactarius indigo / Blue milk mushroom

A striking blue milk cap whose cut gills bleed blue latex that slowly stains green.

Photo: Javier Hernandez, CC BY
Compiled by Mushroom Forage Map field deskExpert review pendingContent checked
Identification warning

Confirm the blue latex. Blue color alone can fade in older specimens.

Season
Summer to autumn
Habitat
Oak and pine forests of eastern North America, Mexico, Central America, and parts of Asia
Underside
Crowded blue gills that stain green
Spore evidence
Cream

Where it grows

Tracked records and known growing zone

Explore on the field map
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Squares: where people recorded it, brighter where more people did
Verified records
8,433
People who recorded it
5,373
Most records (northern hemisphere)
Jul–Sep
Records span
1985–2026

Research-grade iNaturalist records, snapshot Aug 27, 2026. The growing zone combines areas where different people have repeatedly verified it. Records show where people looked and found it, not current abundance or permission to gather.

Observation season

When field records occur

Choose a hemisphere · All recorded years; not a current forecast.

Choose the hemisphere you want to study. Country detection is approximate and some countries span the equator.

Compare before concluding

Lookalikes to rule out

Silver-blue milky

harmless

Lactarius paradoxus is grayer with wine-red to purplish latex rather than blue.

Blue webcaps

caution

Violet Cortinarius have a cobwebby veil and rusty-brown spores, and no latex.

Faded indigo milk caps

harmless

Older caps can look silvery; cut the gills to check for blue milk.

Identification

Everything about the fresh mushroom is blue: cap, gills, stem, and flesh. The cap has concentric darker zones and becomes funnel-shaped with age. Cut the gills and a blue latex appears; wounds slowly turn green. Older, sun-faded caps look silvery gray, so the latex is the key check.

Uses and ecology

Indigo milk caps form mycorrhizal partnerships with oaks and pines. They are sold in markets in Mexico and Guatemala. The flesh is somewhat grainy and holds its color best when sliced thin and cooked quickly.

Memorable fact

The blue pigment is an azulene compound, one of the few natural blue pigments found in mushrooms.

Sources

Never eat a mushroom from this page alone

Confirm identity using the whole specimen, multiple reputable sources, and a qualified local expert. Identified edible species still require appropriate preparation. Cooking does not make a poisonous mushroom safe.

Safety and poison response
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