Lactarius Torminosus - Ecology and Distribution

Ecology and Distribution

Lactarius torminosus is a mycorrhizal species, and as such plays an important role in facilitating nutrient and water uptake by trees. It grows in association with birch (Betula) and hemlock (Tsuga) in mixed forests. It is also known to grow in urban settings when birch trees are nearby. A field study in Scotland concluded that the species is more likely to be present in older than in younger birch woodlands. Fruit bodies grow on the ground, scattered or grouped together. They are a component of the diet of the red squirrel, and serve as breeding sites for some fungus-feeding flies in the Drosophilidae and Mycetophilidae families. Lactarius torminosus mushrooms may be parasitized by the mold Hypomyces lithuanicus, which produces a cream-ochre to cinnamon-colored granular or velvety growth of mycelium on the surfaces of the gills and causes them to be deformed.

The species is found in northern temperate and boreal climates, penetrating sometimes into subartic regions. It has been recorded from North Africa, northern Asia, Europe, and is common in North America, where it sometimes grows with aspen (Populus species). The North American distribution extends north into the Yukon and Alaska and south to Mexico.