Assessment Notes

Justification

Ramaria aurantiisiccescens is an uncommon but widespread species in the Pacific Northwest, northern California and the Rocky Mountains; currently known from ~40 localities. Habitat requirements remain largely unknown, and preliminarily phylogenetic research has shown multiple species with the name R. aurantiisiccescens applied. However, given its broad distribution range, its population size likely is too large to trigger a threat category. Based on current information, it is assessed as Least Concern.

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Taxonomic notes

Preliminarily phylogenetic research has shown multiple species with the name Ramaria aurantiisiccescens applied; thus more work is needed. Field identification of Ramaria is often very difficult, with macromorphological differences being subtle and often intergrading (especially in older sporocarps).

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Geographic range

Ramaria aurantiisiccescensis is known from southern British Columbia, Canada south through the Coast Range into northern California, USA, and the Cascade Range into southern Oregon (MyCoPortal 2024). It is also reported from single sites in northern Arizona and Colorado (MyCoPortal 2024).

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Population and Trends

The species occurs over a widespread area from British Columbia into California, with continuous records in the Cascade Range, and some disjunct outliers in northern California, /Arizona and Colorado. Currently it is known from ~40 sites (Siegel et al. 2019, MyCoPortal 2024). Data to fully assess its population size and trends are lacking. However, despite the challenge in identifying species of Ramaria, given its broad distribution range, its population size likely is too large to trigger a threat category.

Population Trend: Unknown

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Habitat and Ecology

This species is found solitary or scattered on ground. It is ectomycorrhizal with conifers, especially fir (Abies spp.), Western Hemlock (Tsuga heterophylla) and Douglas-fir (Pseudotsuga menziesii). Fruiting occurs in fall. Data to assess habitat preferences is lacking, and although this species appears to have a preference for mature and old growth forests, it does not appear to be restricted to this habitat.

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Threats

Droughts, along with forest management practices has made western forests highly susceptible to stand replacing forest fires. Fire is big threat to this species’ population. A stand replacing fire could severely degrade and/or diminish its current range.

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Conservation Actions

This species is included on the United States Forest Service Northwest Forest Plan Survey and Manage list of rare/old growth forests dependent fungi, and has been actively surveyed for since the late 1990’s (Castellano et al. 1999). The Oregon Natural Heritage rare fungi list (Oregon Biodiversity Information Center 2019) list it as a S2S3 species, and the Washington Natural Heritage list it as a S1 species. Modern taxonomic research on Ramaria is needed along with field surveys to have a better understanding of population trends and habitat requirements of this species, especially if it is restricted to mature and old growth forests.

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Use and Trade

No use/trade is known.

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Source and Citation

Mueller, G.M. & Siegel, N. 2025. Ramaria aurantiisiccescens. The IUCN Red List of Threatened Species 2025: e.T198478523A198488438. Accessed on 23 November 2025.

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• Country occurrence