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Pictorial Key to PNW Mushrooms - Instructions


OK, you just found a mushroom. What is it? These pages are meant to be one convenient location to help you ID your mushroom and easily compare some similarities and differences between species. They are not meant to be used as a replacement for a dichotomous or synoptic key, nor are they meant to replace the use of a good field guide. I do not provide a way for you to quickly arrive at an ID by picking the best of two answers to a series of questions. In fact, you will probably find it rather daunting to jump right in with a mushroom to identify, as there are often many choices to consider at each step. You will be better served if you read the index and group pages as if this were a guide book, to familiarize yourself with how I have grouped the mushrooms together so that when you are ready to try and identify a mushroom, you will already be somewhat familiar with the process. Some group pages are quite large. You may have to spend some time considering all of the different sections of the page you are on, but the upside is that by being presented with all of the likely choices for your mushroom, you are less likely to arrive at a dead end.

My main goal is to present this information in the way that I wish it was presented to me when I was learning, with similar species side by side for comparison and a concise summary of their differences (I have used bold text for the most important points so you can quickly see the features that make a species unique).

Another goal is to teach taxonomy while you learn the mushrooms, which means showing how the different mushrooms are related to each other. I find that particularly interesting. How can we predict which mushrooms are also edible, or which might also have special medicinal value, or which might also help clean up the environment if we don't know which mushrooms are related?  Once you know a mushroom's identity and closest relatives, everything else can be looked up in a text book. In fact, you will need to consult another guidebook for almost anything else you want to know about the mushroom, because providing comprehensive information about a mushroom is not one of my goals.


Colour Codes for Scarcity - Most of the mushrooms you find, at least at first, will likely be colour coded green or blue (the scarcity colour on this web page, not the actual mushroom). Although finding an uncommon or rare mushroom should always be questioned to make sure you haven't misidentified a common species, it does happen and you can expect to find some unusual specimens once in a while. This is highly subjective and somewhat biased towards the Seattle area, based on my experience of trying to notice every mushroom found by over 1,000 PSMS members at all the forays, field trips, ID Clinics and shows for the past 7 seasons as well as at PNW Key Council events and other mycological forays. Which mushrooms are common or rare has not been well studied and is in desperate need of further research. Also, I might mark a mushroom as rare because it only grows in one place in the world, but you might just happen to live there.

Very common. Likely to be found in many locations in most years. Common, at least compared to other similar mushrooms. Uncommon. It is unusual to see anybody find one in a given year. Rare. Unlikely to be found unless you're really lucky.

Perhaps you can start by reading these pages and paying close attention to the blue species. Attempting to use the key to identify a species without having read these pages ahead of time will not be nearly as successful. As you get more and more familiar with the common mushrooms, you can expand your studies to some of the uncommon and rare ones. DO NOT EAT any mushroom you think you have identified using these pages. As much as I'd like to think I've provided a foolproof tool, I haven't, and without years of experience both with many other publications and in the field you are going to make lots of mistakes. NONE OF THESE COLOURS MEAN EDIBLE.



Unless you consult a real field guide after identifying your mushroom here to carefully compare the full description to your specimen, your guess is likely to be wrong. I just don't give enough detail. You should think of these pages as a way to find some starting points to research further, including edibility of a particular mushroom, which I say little about. For heaven's sake, do not eat anything based on what you see here or you could kill yourself!

Try some or all of the following additional resources, and see which work best for you:

Even more valuable than literature for mushroom "book learning" is the hands-on practical experience of getting out there and learning with the mushrooms. Join a local mushroom club, many of which are listed here on the North American Mycological Association website. For instance, if you live near Seattle, you might consider joining PSMS, where there are a wealth of learning opportunities:

It will be easier to identify a mushroom if you have some preparation. Read through these instructions, the introduction and all of the pictorial pages. There are a lot of tips and tricks about ecology, edibility, taxonomy and other topics. They will help you recognize the important features that will assist an identification.



The species name is given under each photograph. Where more than one species look almost the same, I give the names of the different possible species separated by a slash ("/"). You will also see alternate names in parentheses (), which are older popular names used for that exact mushroom (although the name may have been misused). For instance, "Lyophyllum decastes (aggregatum)/loricatum - grey-brown/dark brown" would mean that there are two similar species, Lyophyllum decastes which used to be called L. aggregatum, which is grey-brown, and L. loricatum which is dark brown. Alternate names in () may not always be true synonyms. For instance, "Helvella vespertina (lacunosa)" means that what we now call H. vespertina used to be called H. lacunosa, but that is because we didn't know our species was different from the European lacunosa until recently. They really are two different species, but here in the PNW anything called H. lacunosa was really talking about our local species H. vespertina, so in that sense, they are synonyms.

Single quotes around a name means the name is not official, e.g. Amanita 'alba'. If you see n.p. after a species name, it stands for nomen provisiorum, which means that the species has not been officially named yet, but this is the name that has been proposed.

When more than one species is described in a box, the other species can be assumed to be almost identical except for the differences that are noted. When I compare two species and say that one is "darker", I mean compared to the first species in the box (for boxes with more than one species listed) otherwise I mean compared to the previous box to the left.

Since conifers are so prevalent in most of the PNW, most of these mushrooms, unless otherwise stated, can be found in conifer forests, or conifer forests mixed with hardwoods, either on the ground or attached to the wood. If the mushroom is primarily only found under or on hardwood trees, that will be noted. Ecology is very important in determining the identity of a mushroom, so make sure to take careful note of the habitat. A good trick for figuring out if a mushroom that somebody gave you grew from the ground or on wood is to notice if the stem is curved or not, as if it grew out of the side of something and then curved upwards. But of course this test is not infallible.

Most of these mushrooms can be found in fall, although the PNW has a smaller season in spring. Notable spring fruiters will be noted. Mushrooms that prefer high elevations in the spring and are usually found near melting snow are called snowbank species. Species mostly noted from British Columbia will be called "Northern species", and species mostly from Oregon into California will be called "Southern species".

I have made my descriptions very concise for easy reference, but that means that every word is important, so please read everything carefully, including the general description of that genus or group of species, as well as everything at the top of the page. Each mushroom will vary quite considerably and generalizations given in a description don't always apply. For instance, I only show one picture for each mushroom, and the description might tell you other colours you might find. If I use words like "usually", "said to be" or "maybe" then a character is especially unreliable. Do not expect to always come up with a definite ID, expect instead to find a small number of choices that can form the starting point for further study. Once you have made your guess, why not post your photo and your guess online on the "PNW Mushroomers" Yahoo newsgroup or on "MushroomObserver" (described under Resources above) and perhaps other people in your community can comment and you will find out if you are likely to be correct or not.

All size measurements are controversial. All published authors give a range of sizes, but it is not uncommon to find a mushroom that looks like a world's record, either smaller than the smallest known example or larger than the largest known example. It happens all the time. Such great variety is found in nature that the smallest and largest found by the mycologist who described them are just not likely to be the real size limits. The sizes given here are for full grown specimens and represent the average largest size you can expect to find in a group. If you only find one mushroom, all bets are off. It is going to be especially difficult to choose the correct category when they are delimited by size. It would be extremely useful for somebody to figure out the average size (along with, say, one standard deviation) of each species and publish that. Then size measurements might have some value, but unfortunately, the way things are today, don't take any size measurement you see too seriously.

In these pages you will often see a mushroom described as belonging to a species "group" (or "grp"). This means it is something close to that species, but we have reason to believe that there are other closely related species in the group that are hard to tell apart. Also "sp." refers to a species that has not been identified, and the plural is "spp.". For instance, we might say "Here is a photo of several Hygrocybe spp."

The term cf. (confer) means "compare with". It looks like something, but we're just not sure if it really is or not. You will also see the terms s.l. and s.s. which stand for "sensu lato" (in the wide sense) and "sensu stricto" (in the narrow sense). For instance, Lepiota was a genus of often scaly, free gilled, white spored mushrooms that all seemed related, but as more analysis was done, we realized that they were not all that closely related, and they were split into several different genera. But sometimes it still makes sense to think of them all together as a group, like my page on Lepiota, so we call Lepiota s.l. the wide sense of Lepiota, including many things like Lepiota but not strictly Lepiota. We call just the few mushrooms that are still members of the genus Lepiota Lepiota s.s. This is one of the issues that comes up when you only have 6 levels in the ladder of the tree of life. Sometimes you want to talk about a group of mushrooms that is, say, bigger than a genus but smaller than a family, so you need to come up with a term for that, which is what Lepiota s.l. is.

If you look at the Latin chart below, you will see that certain suffixes are used to show you what level of classification a word belongs to. For instance, ''-aceae" is the suffix for all the families, and "-mycetes" is the suffix for all the classes. So "Hygrophoraceae" is the family that Hygrophorus the genus belongs to.

You will also see words that end in "-oid", for instance I use the term "Marasmioid". This is another group of mushrooms that is not any of the official levels. This can be confusing because it might refer to two different concepts. Mushrooms might be grouped together because they look alike (share the same stature - lower case "marasmioid") even though they are not related. Alternatively, they might be grouped together because they are actually related (said to be in the same "clade"), but the size of the group is not one of the official levels (upper case "Marasmioid" - in this case a group bigger than a family but smaller than an order). Therefore "marasmioid stature" means unrelated mushrooms that just happen to look like a Marasmius, and "Marasmioid clade" means related mushrooms proven to be related through DNA analysis.

I also use the term p.p. which means "pro partem" or "part of". If a page has some of the waxy caps (Hygrophoroid clade mushrooms) on it, but not all of them, I will describe the page as containing Hygrophoroid p.p.

Example:  "Lepiota s.l. p.p."  This contains only a part of the entire group of mushrooms that used to be called Lepiota.


Spore Prints and Gill Attachment

For gilled mushrooms, the most important two questions you are going to be asked over and over again are the colour of the spores and how the gills attach to the stem. There are so many similar gilled mushrooms in the world that they are the hardest to identify, so we need to know more about them. Non gilled mushrooms tend to be easier. But for gilled mushrooms, you're going to need to take spore prints and when there is no time for that, you will eventually learn to get clever about guessing. A spore print is made by removing the cap of the mushroom, and setting it down on paper, ideally both white and black, and leaving it for a few hours (or overnight). If the mushroom is just the right age and in good shape, the spores will be ejected onto the paper and make a very pretty pattern. You use black paper to see if there are very pale coloured spores and white paper for everything else. A good trick is to put the mushroom on a glass slide. Then you can move the slide onto different coloured pieces of paper or even place it under a microscope to look at the spores. When taking a spore print it might help to spritz the mushroom with water first to keep it moist and to cover it with an upside down bowl or glass to keep the moisture in.

Small mushrooms are going to be especially hard to spore print, because they dry out quickly (and are likely dry by the time you find them) and there's not much area to spore print in the first place.  A young mushroom will never disclose its spore colour! It can be hard to tell if something is young, but cap-and-gill mushrooms will sometimes have a hemispherical cap when young and a flat cap that has opened up when older. For a young mushroom, there will be no spores to spore print, and no clues to look for. In these cases, you will just have to try all four colour categories.

(Click to enlarge)

When asked to pick a spore colour, you are going to be asked to place it in one of the four categories: Pale (white to yellow maybe with a hint of pink), Pink (salmon), Dark/Cold Browns (dark chocolate, purple brown to black), or Warm Browns (ordinary brown, light brown or rusty-orange brown).

Underneath each spore colour is the chapter in David Arora's Mushrooms Demystified where you can find families of mushrooms with that spore colour. I also warn you if that chapter is big (the Tricholoma and Cortinarius chapters). Note that mushroom taxonomy has changed since his book came out and the mushrooms are no longer categorized the way he does it. (More information in the introduction and taxonomy pages).

To save time, you will eventually learn how to make an educated guess about the spore print colour without always having to make a spore print, but please continue to make spore prints to test your guesses until you are very experienced. Looking at the gills will sometimes tell you the spore colour if the gills are white but if the gills themselves are coloured you can not reliably tell the spore colour. A good trick to learn is to look for spores that have fallen onto the cap of a neighbouring mushroom or gotten stuck on the edge of the cap or on the mushroom's stem. The cobweb veil remains found in Cortinarius and many other genera are particularly good for catching spores. Another good trick if you have a large group of the same mushroom is to notice the difference between the gills of younger ones that haven't developed spores and older ones which have. Getting experience at guessing the spore print colour is one of the most important things you will have to learn. Realizing when you can't tell (and not getting it wrong) will be equally important.

Purple black spores have fallen from the top mushroom onto the lower one.



Orange-brown spores have been caught in the cortina along the cap edge and stem. The gills are covered in orange spores too, but you can't tell!

Gill attachment is the second important thing to know about a gilled mushroom. The gills run from the edge of the cap to the stem, but how do they touch the stem? The most general choices are:

Free - they don't reach the stem, they take a last minute turn up into the cap. Tip: the stem will often come off easily without damaging the mushroom.

Notched/Adnexed - the gills turn towards the cap as in free gills, but they actually do connect to the stem. (The difference is subtle and not covered here).

Adnate - The gills simply go in a (relatively) straight line into the stem.

Decurrent - the gills run down the stem. The chanterelle is famous for this look, although they are not truly gilled like this false chanterelle.

There are other more subtle choices that lie in between these choices, like "short-decurrent" or "arcuate" (turning towards the cap but ending up decurrent, as in some Mycenas) but for simplicity's sake it is best to begin by understanding these four choices, just like it is best to begin by placing all the different spore colours into one of four categories. Even simpler, it is often useful just to know if the gills are free or attached (by any of the above methods).

Don't be fooled by the gill attachment! Sometimes it is hard to tell the difference between free and adnexed (e.g. Amanita) and sometimes a mushroom that has grown or been handled can have the gills break off the stem and look free, so be sure and look for the little striations at the top of the stem that would show that the gills used to attach there.


Naming a mushroom

All mushrooms have a scientific name in Latin. Many mushrooms also have a common English name (or names in many other languages) but it's not always a good idea to use these names. There are different common names for the same mushroom. Some common names are used for more than one mushroom. Only a small percentage of mushrooms even have common names, so there often just isn't one to use. So we chose Latin because nobody actually speaks it so we are being equally mean to everybody by not picking anybody's native language. The downside of this is that since there are no native speakers still alive, we can't ask anyone how to pronounce Latin, so you might hear as many different pronunciations as you hear speakers, but don't worry about that too much. There are a few favoured ways to say things, and you will just have to listen to those around you and make a decision.

The tree of life is divided up into hierarchical levels. At the top we have the Kingdom of fungi. This is analogous to the kingdoms of animals and plants (although there are many more kingdoms than that). The Kingdom is divided into a few Phyla, and each Phylum is divided into Classes, then Orders, Families, Genera and Species. A good way to remember this is with the saying "King Philip Comes Of Fairly Good Stock", or something similar. The choice of six levels to divide up the kingdoms is completely arbitrary, and can't tell you the whole picture, which is why some people don't like it, but we arguably don't have a better system yet.  Here is the full classification of everybody's favourite looking mushroom, the Alice in Wonderland or Mario Brothers video game mushroom:

Phylum (plural Phyla) - Basidiomycota

Class - Agaricomycetes

Order - Agaricales

Family - Amanitaceae

Genus (plural Genera) - Amanita

Species - muscaria

Every name is capitalized except the species name, which is lower case.

This is too long to write out every time, so we just say "Amanita muscaria", the Genus and Species part. If you want to know the rest, you have to go look it up.

We can't just use the Species name because many mushrooms have the same species name. There is, for instance, a Chrysomphalina aurantiaca and a Hygrophoropsis aurantiaca (aurantiaca means orange).

Definitions of terms used in the pictorial key

I often use the term "viscid" to describe the cap, which means sticky when wet. One way to tell is to give it the "kiss test". Give a bunch of little pecks to the mushroom cap, moistening it, and see if it kind of sticks to your lip or tongue. Another way is simply to note whether or not debris is stuck to the cap, this often indicates that the cap used to be wet and sticky.

Other cap terms are umbonate, which means a pointy cap with a nipple in the centre (in extreme cases called papillate) and umbilicate which is the opposite, with a depression in the centre of the cap. Striate is a term that means the cap is somewhat translucent and you can see through to the gills underneath which make radial lines around the edge of the cap.

Hygrophanous means that the mushroom cap changes colour when it dries out. As it dries, some parts of the cap will become much paler, and soon the whole cap will have changed from a darker to a lighter colour.




Mushrooms have many different interesting odors, but one in particular that comes up a lot that is not obvious is farinaceous. This is the odor of meal, raw bread dough or cucumber rind, but you will have to smell it for yourself in a mushroom before you will know exactly what I am talking about. This and other odors may be hard to detect - you may have to crush a bit of the mushroom to bring out the odor and if it is small and you only have one of them, you will end up sacrificing the whole thing to discover its odor and taste.

If a mushroom stem does not come out of the centre of the bottom of the cap, we call it an eccentric stem (off-centre) or a lateral stem (coming out of the side of the mushroom).

Some mushrooms have a partial veil connecting the edge of the cap to the stem. As the mushroom grows and the cap expands from convex to flat, this protective veil breaks. By this time, you may no longer be able to tell there was a partial veil. Or perhaps there will be remains of some tissue hanging off the edge of the cap or around the stem forming a ring. Some mushrooms also have a universal veil that covers and protects the entire mushroom when young, leaving behind tissue or slime in other places, such as a volva at the bottom of the stem, as you will see when you browse the various groups.

An almost intact young veil.

Veil remnants on cap.

Veil remnants leaving a ring on the stem.


Although this is meant to be mostly a macroscopic key, I will note interesting microscopic characters of certain mushrooms as well as interesting colours that a mushroom (either to the naked eye or under a microscope) might turn if various chemicals are applied to it. Although it's impractical to look at the spores in the field, it is practical to carry a few chemicals with you to test things with.


For more information, please read the Introduction.

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