Described as Cortinarius orichalceus var. olympianus f. luteifolius (Smith 1944) from a 1941 collection made near Lake Angeles, in the Olympic National Park in Washington. It was later elevated it to species rank, as Cortinarius luteicolor (Liimatainen, et. al. 2014).
Cortinarius species are notoriously hard to identify, and this species is no exception. Cortinarius oliveopetasatus and C. subsulfurinus are very similar macroscopically, but differ by the brown KOH reaction on the cap, vs. a red reaction for C. luticolor (Adams 2020).
Cortinarius luteicolor is a rare species, known from seven small and disjunct populations in the western North American mountains. It appears to be restricted to old growth forests.
Widespread, but scattered in small and disjunct populations in the Pacific Northwest and California mountains. Currently known from seven collections, from California, Oregon, Washington, USA, and British Columbia, Canada (Siegel et al. 2019).
Currently known seven collections; a single high elevation site in the central Sierra Nevada in California, and scattered mid to high elevation sites in the Cascade and Olympic mountains in the Pacific Northwest. Little is known about the habitat associations of this species. Based on the few collections made, it appears to be restricted to mature and old growth forests, which are under threat from fires, logging and climate change
Population Trend: Decreasing
Solitary or scattered; often in small patches in soil or duff; fruiting in fall. Ectomycorrhizal with conifers, and likely restricted to old growth forest. (Siegel et al. 2019). A recent collection from California was from old growth Abies and Pinus in Yosemite National Park in California, and a collection in WA was in old growth Abies, Tsuga and Pseudotsuga (S. Adams, personal communication). The other five sites are scattered mid to high elevation sites in the Cascades and Olympics in the Pacific Northwest, but no habitat notes accompany the collections.
This is a ectomycorrhizal fungus species dependent on living host trees for viability. The major threat to this species and its co-occurring co-generic brethren is habitat destruction, via the logging of old-growth forests to which it appears confined too. The extent of old growth forest in the Pacific Northwest of North America has declined 90% in the last century (Society of American Foresters 1984, Haynes 1986).
Fire is big threat to this species’ populations. A stand replacing fire could severely degrade and/or diminish its current range. Logging and machine clearing of understory vegetation should be limited in mature and old growth forest in areas where this species might occur.
This species should be added to the United States Forest Service Northwest Forest Plan Survey and Manage list of rare/old growth forests dependent fungi.
Surveys for additional populations of this species. Better understand and describe habitat limitations of this species.
Adams, S. 2020. https://nacorts.com/2020/09/07/cortinarius-oliveopetasatus/
Haynes, T.W. 1986. Inventory and value of old-growth in the Douglas-fir region. PNW-RN 437. U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station, Portland, OR.
Liimatainen, K., T. Niskanen, B. Dima, I. Kytövuori, J.F. Ammirati & T.G. Frøslev. 2014. The largest type study of Agaricales species to date: bringing identification and nomenclature of Phlegmacium (Cortinarius) into the DNA era. Persoonia 33: 98–140.
Siegel, N., Vellinga, E.C., Schwarz, C., Castellano, M.A. and Ikeda, D. 2019. A Field Guide to the Rare Fungi of California’s National Forests. Bookmobile: Minneapolis, MN. 313 p.
Smith, A.H. 1939. Studies in the Genus Cortinarius. I. Contributions from the University of Michigan Herbarium. 2:5–42.
Smith, A.H. 1944. New and interesting Cortinarii from North America. Lloydia. 7:163–235.
Society of American Foresters. 1984. Scheduling the harvest of old growth : Old-growth forests in the Pacific Northwest : a position of the Society of American Foresters and Report of the SAF Task Force on Scheduling the Harvest of Old-Growth Timber. . Bethesda, MD.