Assessment Notes

Justification

Chroogomphus tomentosus is a common species in hemlock forests of northern California, the Pacific Northwest, and into south-central Alaska. No decline has been recorded; it is assessed as Least Concern (LC).

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Taxonomic notes

It was described as Gomphidius tomentosus, from a Washington, USA type collection (Murrill 1912), and later transferred into the genus Chroogomphus (Miller 1964), where is resides today.

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Geographic range

This species is widespread in western North America; on the coast, it occurs from Sonoma County in northern California, USA, north into south-central Alaska. In the mountains, it occurs from the southern Cascade Range in Oregon, north into British Columbia, Canada, with scattered records east into the northern Rocky Mountains.

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Population and Trends

The population is widespread, and it is a very common species. No decline has been recorded.

Population Trend: Stable

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Habitat and Ecology

Chroogomphus tomentosus has an obligatory relationship (likely as a parasite) with Aureoboletus mirabilis, which in turn is ectomycorrhizal with hemlock (Tsuga spp.). It is especially common in the Pacific Northwest into southeast Alaska, with fruiting in late summer and fall.

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Threats

No specific threats have been identified with regards to this species.

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Conservation Actions

No specific conservation actions have been identified with regards to this species, and no specific research is needed with regards to this species.

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Use and Trade

Chroogomphus tomentosus is edible, but only occasionally collected for food.

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Source and Citation

Siegel, N. 2022. Chroogomphus tomentosus. The IUCN Red List of Threatened Species 2022: e.T198479395A198488912. Accessed on 21 November 2025.

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• Country occurrence