Assessment Notes

Justification

Lactarius aurantiosordidus is a small, dingy coloured member of the Lactarius 'deliciosus' group growing with Sitka Spruce on the Pacific Coast from northern California into Alaska. Because it belongs to a difficult to distinguish complex of species, data to assess trends and total population is lacking, but its widespread occurrence and local abundance suggest that it should be listed as Least Concern.

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Taxonomic notes

This species was described from northern California (Nuytinck et al. 2006). Some collections appear to have been called Lactarius deliciosus var. olivaceosordidus (Hesler and Smith 1979, Methven 1997).

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Geographic range

This species is known from coastal forests from northern California into south-east Alaska, roughly following the distribution of Sitka Spruce (Picea sitchensis) (iNaturalist 2021, N. Siegel unpublished data).

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Population and Trends

The population is widespread, but being a recently described and hard to identify species, data to assess trends are currently lacking. It is locally common to abundant on the far northern California and Oregon coast, and also seen with regularity in Alaska (N. Siegel unpublished data).

Population Trend: unknown

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Habitat and Ecology

It is ectomycorrhizal with Sitka Spruce (Picea sitchensis) in coastal forests. Fruiting occurs in summer in the north, into late fall in the southern portions of its range.

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Threats

Climate change is affecting Sitka Spruce forests on the southern portion of its range; but probably not at a scale to affect the population overall. Widespread logging in British Columbia, Canada and south-east Alaska, USA, could be having an impact on the species.

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Conservation Actions

Mature and old growth spruce forests in British Columbia and Alaska should be protected. Population data from across the range of the species are needed to assess trends.

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Use and Trade

This species is edible, but appears to be rarely collected.

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Source and Citation

Siegel, N. 2021. Lactarius aurantiosordidus. The IUCN Red List of Threatened Species 2021: e.T195922353A195926447. https://dx.doi.org/10.2305/IUCN.UK.2021-2.RLTS.T195922353A195926447.en .Accessed on 30 September 2022

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• Country occurrence