Michigan
Mushroom Hunters Club

(2010) September Mushroom of the Month is...

Laccaria ochropurpurea: the purple gilled Laccaria

Laccaria Ochropurpurea Laccaria ochropurpurea

In Michigan we already call one mushroom the pink bottom (Agaricus campestris). If I were to provide a common name for this mushroom, I would call it the purple bottom. The purple gilled Laccaria is an unusually shaped gilled mushroom especially when young. I have seen young fruiting bodies with ¼ inch wide caps on a 3/4 inch wide stem. Even when mature the stem often seems rather long and even somewhat wide for the cap size though there also are more normally appearing specimens.

The cap of a mature purple gilled Laccaria is two to seven inches wide with a stem two to eight inches high. The cap is slightly depressed at the center. The cap is purplish to brownish purple when very young but soon fades to a silvery or grayish white with age. The wide spaced gills are attached and sometimes slightly decurrent (coming down the stem). Laccaria ochropurpureaThe gills are a lovely purple shade both in young and mature specimens. Sometimes the gills in mature specimens appear white spotted from the spores. The stem can be 3/8 inch to ¾ inch wide with a curve near the base. The stem, streaked with purple or brown fibrils, is quite fibrous and should be removed prior to cooking mature specimens. With young specimens the stem is edible and not quite so fibrous. The mushrooms are found singly or in small groups in grassy areas near oaks as well as in oak forests.

Laccaria ochropurpurea A young specimen of
Laccaria ochropurpurea

Laccaria ochropurpurea Note the variety of shapes and sizes in these young specimens

Laccaria ochropurpurea is a good edible though it has not received much attention from the mycophagist public. On its own sautéed in butter, this mushroom makes a mediocre side dish but its firm texture makes it very suitable for stews, soups and sauces. Fischer and Bessette in Edible Wild Mushrooms of North America do provide a recipe for “Pork with Purple Laccaria and Plum Sauce”.

There are somewhat toxic species of Cortinarius that superficially resemble the purple gilled Laccaria. The Cortinarius species will have a rusty brown spore print whereas the purple gilled Laccaria has a white spore print. The Cortinarius species when young will have a cobwebby partial veil, a cortina, which will leave minor remnants in a ring on the stem that will collect spores as the mushroom matures. The purple gilled Laccaria has no suggestion of a ring at any stage. As the purple gilled Cortinarius species may be toxic, it is important to take spore prints as you’re learning this mushroom. No Cortinarius has a stem as fibrous as that of the purple gilled Laccaria so this is also a distinguishing feature.