© Steve Trudell

Back to Main Menu

Danny’s DNA Discoveries – Russula of the PNW
by Danny Miller

Click here for my Pictorial Key to Russula

Brevipes and Compactae Clades - click to expand

These two clades of Russulas are easy to recognize, and used to be thought of as one group, but they form two separate genetic clades.

  • completely white when young (other Russulas have a coloured cap cuticle and may be whitish, but not usually this white)
  • stain brown in age, sometimes a lot
  • quite dense (thus the term "compact") and heavy
  • have subgills (shorter gills that don't go all the way from stem to cap, most other Russulas don't)
  • there is no top cap layer to peel off easily (there is a coloured cuticle on most other Russulas that peels, at least somewhat)
    • Compactae: these turn black in age, sometimes with an intermediate red phase. It can be quite striking!
    • Brevipes: do not, but they brown considerably in age.

Species mentioned: Russula cascadensis, brevipes, nigricans, dissimulans, albonigra, atrata, adusta, densifolia, acrifolia, anthracina

Fetid Russulas - Ingratula and Crassotunicata Clades - click to expand

They taste somewhat peppery, which is bad enough, but even worse than that, they often have a putrid or nauseating odor and flavour.

  • most of them have a yellow-brown to brown cap cuticle with a strongly striate margin
  • often taste somewhat peppery. Ingratula have a putrid, nauseating odor and flavour
  • some brighter yellow-brown ones smell nauseatingly sweet like marashino cherries, the plain brown ones do not.
  • if you cut a fresh stem lengthwise, you may find hollow diamond shaped chambers inside (true for many species in both clades).
  • Crassotunicata has a small, white spored, bright yellow member (which is easily mistaken for core clade species) and an odd one out that is white (but browns considerably) with a very thick, peelable gelatinous cap cuticle.

Species mentioned:  Russula cerolens, sororia, pectinata, pectinatoides, granulata, recondita, laurocerasi, fragrantissima, foetens, pallescens, farinipes, crassotunicata

Heterophyllidia I and II Clades - click to expand

This group needs the most study. They are difficult to identify and not much is known about them. That’s unfortunate, because most if not all of the group members are mild tasting and especially dense and crunchy textured making this group potentially among the better tasting Russulas (although none have been tested enough to be sure of their edibility). There at least a dozen species, and few of them have been named yet or even have a good description. Here is a not-at-all foolproof way of trying to identify this section:

  • spores white to cream (not usually that dark of a yellow)
  • mild tasting and often dense
  • sometimes the caps are matte or even pruinose (but not always) instead of shiny and sticky, which is quite beautiful.
  • gills might be flexible and buttery instead of brittle.
  • more often in brown, green and grey colours, only rarely the red wine colours you see in other Russulas
  • the flesh may or may not brown in age and usually there is no coloured stem flush, but that’s not always the case.
  • the microscopic spot where the spore attaches to the basidium is small and doesn’t darken in iodine as much as it does for other Russulas
So... a Russula with a matte, pruinose or powdery cap might be one of these (except the very common purple capped Russulas in the R. murrillii group). Any green Russula, even with a shiny cap (middle photo), might be one of these. That can be really subtle, a wet cap can hide the matte-ness and any dry cap might start to look matte. Brown, pruinose caps are common in this group.

Species mentioned: Russula brunneola, heterophylla, virescens, smithii, aeruginea, mustelina, medullata, vesca, parazurea, atroglauca, grisea, malva, cyanoxantha

Archaeae, Malodora and Glutinosae Clades

We do not appear to have any Russulas from these sections in the PNW, so we’re not going to learn anything about them today. If you can find one, you’ll be famous.

Core Clade - click to expand

The “core” species (most closely related to the official first Russula, Russula emetica), are not recognized so much by how they look, but by the fact that they are often hot tasting and don't belong to one of the previous groups. A surprising number of species come in either poppy red or yellow (or a mixture, left photo). Some species have a lot of stem flushing (right photo). Unfortunately, the chemical that makes them taste hot can go away or wash out, so sometimes they taste mild. A drop of sulfo vanillin will usually turn the flesh of a “hot” species purple (in this clade or elsewhere), even if a certain specimen tastes mild. This was one of the most interesting results of Anna’s study of Ben’s chemical tests on his Russula collection.

  • any white spored Russula not found in previous sections is probably in this section, whether or not you can detect the hot taste.
  • hot Russulas with cream spores are usually found here. Make sure to rule out the very common, darker yellow spored R. mordax (and the rarer purple/red, spruce Russulas R. firmula and R. ‘punicea’, and R. versicolor), found in the Crown clades below
  • a core clade cream spored Russula that doesn't taste hot is going to be difficult to identify; you'll have to learn their individual characters

Species mentioned: Russula emetica, silvicola, bicolor, hydrophila, griseascens, montana, crenulata, betularum, nana, cremoricolor, raoultii, parapallens, fragilis, phoenicea, hypofragilis, atropurpurea, lilacea, stuntzii, laccata, viscida, americana, rosacea, rosacea var macropseudocystidiata, rhodocephala, sanguinea, sanguinaria, queletii, sardonia, torulosa, salishensis, pelargonia, pseudopelargonia, renidens, albidula, persicina, alcalinicola, exalbicans, gracillima, flava var. pacifica

Crown Clade - click to expand

The remaining Russulas have not been definitively separated out into smaller groups yet, unfortunately, and there are a lot of them. Around half of the Russulas fall into this large clade. There have been many smaller groupings made over the years, but they have not proven to be genetically valid groupings, so I’m going to treat them all as one large group. It gets its name from the fact that they may represent the newest branches, at the “crown” of the genetic tree. I also call them the “garbage” clade, since you can think of these as species that did not end up fitting into any smaller, well defined group, but instead got thrown in to the large garbage bin of clades. They tend to have relatively dark, yellow spores (usually darker than the hot “core” clade Russulas) and are mostly mild, with a few notable exceptions. The many mild species vary a lot in their density, texture and flavour, so some make better edibles than others. Many people indiscriminatly eat all mild Russulas with relatively few reported poisonings, but most cannot be identified reliably so the edibility of most species is still officially unknown. A few species, like the shrimp Russula aff xerampelina are popular edibles. Let's break them down into sub-clades:

Species mentioned: Russula mordax, firmula, punicea, versicolor, veternosa, tenuiceps, xerampelina, viridofusca, isabelliniceps, favrei, elaeodes, olivacea, vinosa, occidentalis, vinososordida, decolorans, mendocinensis, claroflava, flava, californiensis, versicolor, odorata, puellaris, cremeirosea, sapinea, nauseosa, abietina, blackfordiae, sphagnophila, brunneoviolacea, turci, murrillii, postiana, lutea, risigallina, chamaeleontina, olivobrunnea, olivina, intermedia, cessans, lilacea, zelleri, obscurozelleri, pseudotsugarum, graminea, urens, cuprea, nitida, sierrensis, velenovskyi, benwooii, placita, murina, inconstans, maxima, persobria, citrina forma separata

Back to Main Menu