Russula

Russula is a very interesting genus of mushrooms, very different genetically from most other gilled mushrooms and in some sense not really a gilled mushroom at all. (Please read the introductory paragraphs of my Lactarius page for more background information). Russula is similar to Lactarius, but without milk. But unlike Lactarius, which can look quite different from each other, Russulas in the PNW look surprisingly similar. After browsing the illustrations on this page, you should at least be able to recognize a Russula when you see it, if not know which one you have.

You'll notice they all have a certain stature, and they mostly start out entirely white (although the stems can be flushed with pink, and the white can discolor, sometimes dramatically) with the possible exception of a cap cuticle that may be some bright colour. Also important is their brittle texture, like Lactarius, that allows the mushroom to break in any direction it is stressed, resulting in a Russula that is thrown against a tree disappearing into tiny bits instead of long stringy pieces like most mushrooms. This is more fun than it sounds.

Anybody who has worked with Russula will tell you that I am about to try to do the impossible here... tell you how to identify a Russula to species. One of my favourite quotes is from Anna Maria Hussey, from Illustrations of British Mycology in 1855: "If we know of any one, who in the pride of intellect spurned all mental tasks as mere play, we would tame him by insisting on his mastering, classifying and explaining the synonyms of the genus Russula." In other words, if you ever figure out how to identify all the Russulas, rocket science will be child's play. (Other difficult genera are Cortinarius, Inocybe, Psathyrella, Rhizophogon and the entire Entolomataceae family).

One of the main things that separates the Russulas is whether or not they taste mild or like a hot pepper (variously called peppery, acrid or hot, the same as for Lactarius). Chew a piece for 30 seconds to determine the taste, it may get hot slowly! The odor might also be sweet or flowery (like cherries or geraniums), fishy, or putrid like rotting food. Also, how much you can peel the coloured cuticle of cap skin may be important. Russulas are considered "white spored" mushrooms, but the truth is the spore print colour is usually some shade of yellow, from almost pure white to a deep orange-yellow. Unfortunately, the shade of yellow can range dramatically from individual to individual within a species, so I am going to try and avoid making you specify a shade of yellow, but just choose between spores that are white to almost white, or some shade of creamy yellow or darker. When Russulas get old, or scratched, the white flesh may turn yellow, brown, reddish-orange, or grey-black. A few notable species have a pruinose cap, which is dry with a matte finish (not shiny with a glossy finish like most others) and slightly powdery in appearance. These are the important things to take note of. Most Russulas (and Lactarius) appear to be mycorrhizal, so you will usually find them on the ground under certain trees, often conifers (unless otherwise stated).

Russula spores (and thus mature gills) range in colour from white to cream to yellow (sometimes even orange). Make sure you check the oldest specimen you can find.

Unlike "real" gilled mushrooms, Russula have round spores covered in warts that turn black in iodine. Other structures are also round instead of long and stringy.

You might have noticed that nowhere did I say the colour of the cap is important. It's not that I forgot, and it's not that I just assumed you knew that. Russula is also famous for having species with very variable cap colours. Sometimes it matters, but for some species it can literally be almost anything. The pigments are usually water soluble (and can fade to any shade) and the colour is probably also affected by moisture, pH, and who knows what else.

Most Russulas that taste mild are edible, but not incredible. There are exceptions, though. Russula subnigricans has killed people, but it has not yet been found in the PNW, although it has led to a recommendation not to eat its close relatives, the blackening Compactae. California has a close relative that may be deadly. Some of the hot ones have upset some people's stomachs, although, as I explain with Lactarius, most seem to have been eaten successfully after careful preparation. Conversely, some people think that the denser, better flavoured mild Russulas are some of the tastiest mushrooms around, because their brittle texture makes them crunchy instead of tough and chewy like most other mushrooms.

As usual, it is difficult to tell how big the mushroom is in real life from just a picture, so I have tried to indicate when a species is bigger or smaller than a "typical" Russula (5-10cm across). If yours is less than 5cm, consider the "small and fragile" species, and if it is larger than 10cm, consider one of the bigger ones.

Our largest (up to 20cm or more) common Russulas are the Compactae, the fetids, R. xerampelina grp, R. 'olivacea', R. vinosa and R. benwooii. Occasionally members of the heterophyllidia can grow large.

Adnate to decurrent gills. They can be dry or viscid capped. Not hygrophanous. Never a partial veil (locally). Found mostly on the ground.

This page is based on the collections of Ben Woo, a founding member and the first president of PSMS. He collected more than 1,000 Russulas across the PNW over a period of more than 30 years. Many thanks to Anna Bazzicalupo and her team for the critical study and sequencing of Ben's collection that made this page (and any true understanding our Russulas) possible. The species shown on this page are generally those for which we have actual evidence, but this page should not be considered complete. If half the Russulas found in this area can be identified using this page, it will have exceeded its goals. Most Russulas found on forays are never identified. Beware: you will have false positives (uncommon Russulas that look like something on this page, but aren't) as well as false negatives (sometimes the mushrooms described here will NOT have the characters I say they usually have).

Unfortunately, until my key is more complete, you will have to read through the following sections to determine which one most closely matches your specimen. Let's begin.

There are thankfully a number of easy to recognize groups of Russulas, and one of them is the set of compact Russulas.

Compactae turn blackish after a while. Often turning bright orange-red first. Most taste mild.

This group contains some Russulas with very interesting smells, but not all of them have a discernable odor. Most look similar.

R. cerolens ('sororia'/'pectinata'/'pectinatoides') - tannish-brown, somewhat unpleasant odor? Usually with a dark stain in the centre of the cap. Creamy yellow spores. <8cm. With douglas fir.

R. recondita grp - 3 other species may occur as well, perhaps mild and perhaps without the dark centre stain.

R. 'laurocerasi' ('fragrantissima') group - Two species, may get large, brighter yellow-brown than R. cerolens, smells like maraschino cherries/sweet almonds. Creamy spores as well. None of these taste any good.

R. fluvialis ('foetens') - Large, with a nauseatingly sweet odor not specifically like maraschino cherry or almond. <15cm.

R. pallescens ('farinipes') - in a second section, Ingratula II, with R. crassotunicata. Bright yellow-brown with a striate margin, but little odor, the smallest one with the whitest spores. The cap cuticle is harder to peel. Found with conifers (hemlock or spruce)? Tastes much more peppery than the others.

R. crassotunicata - also in Ingratula II. Entirely white to pale yellow. Browns quite a bit and most notably, the cap cuticle is a thick layer of gelatin that peels right off. Occasionally mild. With conifers (hemlock and spruce)?

These are some of the most common Russulas in Europe and sometimes scorned even by Russula standards, but they are not so common over here. They are a distinctive, interesting group, yet it takes practice to recognize one.

R. sp. Woo 16 - A pruinose purple capped Heterophyllidia I species with a flushed stem does turn pink in FeSO4. R. murrillii group members (below) are more fragile and don't have the flushed stem.

R. aeruginea - cream spores, olive-green cap that is shinier than most other species. With doug fir and hemlock.

R. sp. Woo 13 - a truly beautiful matte capped green Russula that can peel more than halfway to the centre.

R. sp. Woo 15 - a matte capped species that often has some green parts, but usually lots of brown too.

R. sp. Woo 14 - a shiny capped species that is tan coloured with some green tints.

R. medullata - cream spores, greyish-olive-brown matte cap, without purple, similar to sp. Woo 15, but the green parts not as distinct. With doug fir and hemlock, or spruce and pine.

R. mustelina - cream spores, pale young cap turning a matte dull brown without green but sometimes with pink or vinaceous tints. Sometimes found barely poking out of the ground. With douglas fir?

Two other greyish-brown, matte capped, cream spored species (#9 and #10) are not well understood and easily confused with the above.

This group, sometimes simply called the "Russula" subgenus, can be recognized by:

R. emetica ('silvicola'/'bicolor'/'raoultii') - cap colours of poppy red, yellow, or both. ~2/3 of 25 specimens studied had red colours (possibly also yellow). The rest were pure yellow. Consistently acrid.

R. montana (griseascens/hydrophila?) - very similar, but the stem tends to grey a bit in age. ~2/3 of 25 specimens were pure yellow (the rest had at least some red).

R. crenulata? - described as just yellow (but may also be poppy red?) with ragged gill edges. Two genetic species exist, one of which may be R. crenulata, but more study is required before we know what this species is and if the ragged gill edges is a consistent character.

R. laccata - a darker wine-red cap (not really poppy red) that fades in places to creamy yellow, found under willow.

R. betularum - pinkish cap that can fade? perhaps purplish, may be found with pine and spruce and birch?

R. 'viscida' - similar, with a stem that browns considerably in age. With conifers and possibly hardwoods.

R. parapallens - pink or yellow or both, but usually not as bright as the others, and often with a splotch of purple brown on the disc. Sometimes mild, or with a pink flushed stem. Related to the cream spored group.

R. stuntzii - whitish with tinges of grey. Lavender colours may be present, but usually with grey (unlike 'fragilis'). Occasionally mild. Slight buff tinge to the spores. Also related to the cream spored group.

R. hypofragilis ('fragilis') - dark purple, purple-red or purple-brown, but may fade around the edges to white, with the centre usually still coloured. Not as fragile as the true R. fragilis. With mixed conifers, early fall? Sometimes mild.

R. phoenicea ('fragilis') - very similar, but perhaps more likely to have olive colours mixed in. With mixed conifers usually including douglas fir, late fall? Often tastes mild.

R. americana (rosacea var. macropseudocystidiata) - poppy red like R. emetica, with a red flushed stem. May smell like geraniums, early fall? Cream spores. May be mild. With fir and hemlock.

R. rhodocephala ('sanguinaria'/'rosacea') - very similar, perhaps duller red to purplish with less of a stem flush, which may spot yellow. Unlike R. americana, usually only under pine, late fall? Cream to yellow spores. Usually hot.

R. pseudopelargonia ('pelargonia') - reddish-purple cap often with purple centre and a slightly flushed stem which may spot yellow-brown in places. Cream spores. Strong geranium or fruity odor. Found under douglas fir and hemlock west of the cascades. Hot.

R. salishensis ('pelargonia'/'queletii') - very similar and hard to distinguish reddish-purple capped species with possible purple stem flush also fading exposing yellow-olive tones with strong geranium odor, also douglas fir and hemlock, early fall? Cream to yellow spores. Occasionally mild.

R. queletii? ('sardonia'/'torulosa') - purple (but also sometimes fading to expose yellow-olive tones) and most likely to have a purple flushed stem. Cream spores. Fruity or geranium odor. Found with spruce and pine, late fall? Frequently reported as mild.

Three other related often red or yellow species are found, poorly understood, including: R. 'renidens' (#31), R. 'albidula' (#33) and R. alcalinicola.

Finally, the yellow spored species (often darker then the previous group) and not related to this group, but easily confused with it.

The rest of the Russulas are in a subgenus sometimes called the "crown" or affectionately, the "garbage" clade. Let's go through them.

The Russula xerampelina group deserves its own category. They are probably the most common Russulas around and said to be the best tasting (for a Russula, which might not be saying much), but unfortunately they can come in almost any colour. In the space of a single hour, I once saw yellow, orange, brown, green, red and purple ones, although they are "usually" dark purple. So forget trying to ID them by cap colour, you are looking for the following combination of characters:

Actually, if you have a good nose, the shrimp odor is all you need to know. Just give it a sniff where the gills meet the stem, especially a few minutes after scratching them. But for young specimens, or those like me who can't always detect the shrimp odor, you'll need to know the other characters. A drop of FeSO4, if you are chemically inclined, on the flesh of the cap and stem will turn greenish, which is not a common reaction for Russula. (FeSO4 is sold in garden stores as iron sulphate).

Compare them with R. 'olivacea', a fairly close relative, which is similarly large, but has a dryer cap sometimes like kid leather with denser flesh. It does not have an odor, does not (usually) stain as brown and does not (usually) turn green in FeSO4 (although sometimes it does both). Neither does another very common large (but not dense) Russula often mistaken for this one, R. benwooii.

While in many Russulas the flesh, stem and gills will turn from white to brownish as they age, the following two species (not especially related to each other) turn grey. This can be hard to detect, as the reaction may take hours after it has been handled! Many other Russulas will get small grey spots, but these will often (hopefully) eventually turn more grey than most. They may even turn a little red first, but they differ from the blackening Russulas by not blackening (just greying), and by having some kind of colourful cap. They are mostly mild tasting with cream spores (and mature gills).

A few other Russulas that are related to each other turn yellow as they age instead of brown, one of them quite dramatically. Members of the R. rosacea grp, described above, may also do this, but they are usually hotter tasting with a pink/purple stem flush, and never found under birch. This group of mushrooms both have a striate, somewhat viscid cap.

As noted above, some acrid species are sometimes reported as mild, so you may have to check there too if your Russula isn't a good match to one of these. The stems of this group do not usually have a pink flush nor do they brown much in age. If you're sure you don't have one of the species above, here's what you probably have:

1. "Encrusted hyphae" in the cap make the purple capped ones pruinose or matte instead of shiny. Otherwise, a bright yellow cap often indicates this group.

2. The Russula zelleri grp, one of the most common groups. Most other small purple or purplish-red mushrooms are these, sometimes even green.

3. Russula sierrensis - described as a small purple-red Russula under oak and pine from California, it turns out it can be many other colours and live with many different conifers all over the PNW (and have cream to yellow spores). It can resemble many other Russulas and does not yet have a good description to be able to recognize it. Figuring this one out will take some study. It is somewhat related to the greying R. vinosa, but this species does not grey.

Congratulations! You now know more about PNW Russula than most people. Russulas can be an intimidating group to study, so most people do not bother to try and learn more than a few distinctive species, but if you work at it a little bit, you'll soon be able to impress your friends. But don't get frustrated when even with this page, you may still find as many Russulas you can't identify as those that you can. You're in good company. A quick look through GenBank shows that most of the Russulas that are in fact the same species have many different names, and looking at Russulas with the same name shows that many are completely unrelated to each other. For specialized literature for those of you who want to learn more, you will need to learn Italian or French, as there are no comprehensive illustrated English language books about Russula besides Fungi of Switzerland Vol. 6.

Expert links:	Compactae	Fetid
Heterophyllidia	Acrid tasting (emetica/rosacea, etc.)	Shrimp
Greying	Yellowing	Mild, Cream to Yellow Spored