Assessment Notes

Justification

Suillus ponderosus is a common and widespread species in western North America, growing with young to mature Douglas Fir from central California into southern British Columbia. The population is stable; and not subject to any threats. It is listed as Least Concern (LC).

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Taxonomic notes

Described from western North America (Smith and Thiers 1964). Suillus imitatus var. viridescens is a synonym (Nguyen et al. 2013).

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Geographic range

This species is widespread in the Pacific States of North America, from southern British Columbia, Canada, south from coast to Cascade Range in the Pacific Northwest, and coast to Coast Range south to central California, USA.

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Population and Trends

The population occurs over a wide area, and locally is very common. There is no indication of any decline.

Population Trend: Stable

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Habitat and Ecology

It is ectomycorrhizal, associated with Douglas Fir (Pseudotsuga menziesii) in young to mature forest, and urban areas. It is common, especially in young Douglas Fir forests in the Pacific Northwest.

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Threats

There are no major threats to this species. It is common, and found with young to mature trees, in both urban and forested habitats.

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Conservation Actions

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

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Use and Trade

This species is edible, but rarely collected for food.

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Source and Citation

Siegel, N. 2021. Suillus ponderosus. The IUCN Red List of Threatened Species 2021: e.T198479245A198490186. Accessed on 20 November 2025.

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• Country occurrence