Some say there are over 150 species of Agaricus mushrooms. Some say there are more. Mycologists are not sure how many there are. Efforts to identify them end up in a maze of confusion since a given Agaricus can key 90% to seven different species and not completely match anything documented!

I have my own personal theory about Agariuses. It is borne out by some preliminary evidence in the wild where we have been gathering mushrooms.

I think there are a few Agaricus species, with key features.

• Brown Caps
• White Caps
• Gray Caps
• Phenolic Scented (or other Chemical Smells)
• Non-Aromatic (no particular identifying odor)
• Almond Scented
• Anise or Savory Anise Scented
• Fruity Scented

The ONLY part that is important to YOU, is the smell. If they smell good, or nondescript, they are generally good, or nondescript. If they smell bad, they are bad. A lot of GOOD ones will smell BRIEFLY like sweet ink, and then develop an appealing odor. They are good ones. If the stink stays, it is bad. If it starts bad (for 30 seconds to a minute, no more) and then turns good, it is good, BUT requires cooking.

All the rest - yellow staining, red staining, orange staining, fluccuse stipe, smooth stype, cogwheel veil or skirt veil or absorbing veil or evanescent veil, cap shape, stipe shape, size, etc, DON'T MATTER (yellow staining is usually an indicator of the presence of chemicals, but the smell is still the determiner of edibility). I think they are just genetic variations that are completely irrelevant. Because what happens to Agaricus mushrooms is something that MAKES all this irrelevant.

Agaricus are either EDIBLE, or NOT EDIBLE. The smell is what tells you.

Now, some Agaricus are listed as making some people ill, others not. Generally, this means you need to cook that mushroom well if you choose to try it. Much of the time, that is WHY some people experience digestive upset from it and others do not. The rest of the time it is just mistaken ID.

So what is happening out there with Agaricus ID? Why is it that you can always key them 90% to something, usually MORE than one something, but rarely 100% to ANYTHING? And why is it that most descriptions are filled with things like "anise or almond scent" (when they are VERY different smells), and "may or may not bruise yellow", and "stem may be smooth or fluccose", or "stipe may be equal or bulbous"? Why is it that if you find three different descriptions of a single Agaricus mushroom that NONE of them will agree on what that mushroom is supposed to look, smell, taste, and react like?

To answer that, I have to tell a story.

We went into the woods about five times before we spotted our first Agaricus (well, other than Meadow and Horse Mushrooms, which I had become familiar with years before). It was at the base of an aged giant... a Hemlock Tree. I was fairly inexperienced with the genus at the time, but was excited because I knew it was an Agaricus! The brown detached gills and partial veil lingering on the stem were dead giveaways.

I picked two, and brought them home to key them. They keyed quickly as A. Placomyces. Poisonous - with the classic indicators. The base stained yellow, and the mushroom was distinctly phenolic in smell.

A few days later, in another area we found another one. The cap was less grainy in appearance, the color transitions smoother. Otherwise very similar. It keyed quickly as A. Moelleri. Same smell, same cap size, so similar in color and appearance that half the ID'd photos online mixed up A. Moelleri and A. Placomyces indiscriminately, and some said they were the same species.

I recalled that I had read descriptions of both Agaricus Bisporus, and Agaricus Brunnescens several years ago, and had keyed the mushrooms in the grocery store to them - this when I had noticed that they carried two decidedly different species of Portobellos, and I knew that Agaricus Brunnescens had been the original Portobello, until the brown Agaricus Bisporus (same species as the white button mushroom) had taken over in most commercial markets. Certain seasons of the year though, in some areas, Agaricus Brunnescens is still grown since it performs better in some climate conditions.

So I KNEW that they are two different species. I could SEE the difference.

But recently, many online scientific sources now state that A. Bisporus and A. Brunnescens are the same species and one is an older name for it than the other. NOT SO! They are distinctly different! Of course, if you just READ the descriptions, you will not be able to tell that this is so! But if you LOOK at the mushrooms, you can tell immediately that they are not the same species.

A. Brunnescens has a smoother cap coloration, and often a minimally lighter cap color. The stipe is a tiny bit broader. The cap is a very little bit thicker, and WHITER all the way through (Bisporus seems to color gray from the gills much sooner), and Brunnescens stains red more than Bisporus. But most tellingly, Brunnescens has PALE PINK GILLS in the button stage. They do not significantly start to darken until the veil breaks. Bisporus has pinkish gray gills that turn to dark gray to brown gills in the button stage - they start out the same, but Bisporus turns much more quickly, and will be darkened before the veil breaks.

So even among KNOWN DIFFERENT SPECIES, there is a great deal of confusion about what is what! Frankly though, the most important thing to know here is that they both taste about the same and are equally edible. Other differences matter to some people but not others (principally growers and transporters of the mushrooms).

I have seen commercial mushrooms that are decidedly somewhere between the two species. They key out with some features of each.

So we also have scientists who are describing mushrooms, and then another person comes along and says, "Oh, I found that one too, only it wasn't like THAT, it is like THIS." And they change the description because they could not get it to stain yellow, or the stem was smooth instead of fuzzy, or the veil had cogwheels on it or something.

To continue with our story (in which we give the explanation to all of this).

A few days after that second inedible Agaricus, we stumbled on a RED-BROWN capped Agaricus. It keyed out 95% to Agaricus Subrutilescens. Only problem was that the smell was nondescript - but some sources said Subrutilescens smelled Almondy, some said not, some said Anisey, some said not, some said Fruity, some said nondescript. No one agrees on what Subrutilescens smells like. They only agree that the cap is some shade of winey or reddish brown. These were definitely reddish brown. And Subrutilescens does not stain. Or so 80% of the sources said, and ours did not stain.

After about a week of gathering these, we found one one day that was distinctly different! It smelled of Almonds, was smaller with a thin stem, bruised yellow, and had an underlying phenolic smell that disappeared quickly. It keyed to Agaricus Tennuiannulatus. Of course, later it also keyed to about 80% on four other small Agaricus mushrooms... But we stuck with Tennuiannulatus, partly because by then we had finally learned to say it without tripping over it.

And then things got really crazy. It rained. And rained. And RAINED. I woke up with the Pooh song in my head one night, "And the rain rain rain came down down down, and rushed right into Piglet's...". We gathered mushrooms in the rain, and the mud, and the muck. And the rain kept on coming.

I went out one day and gathered Agaricus mushrooms from several areas, and when I got back, it was clear that I had TWO DIFFERENT KINDS in my basket. One was larger, firmer, and had an odor that kept drawing me back to identify it... I knew it, I just could not place it. The longer it lay there, the stronger the odor became.

ANISE! It was Anise... with a savory overtone. This mushroom was reddish, but also had a bit darker brown cap. And the gills were much paler pink for the stage of development than the caps of the ones I had been picking had been.

One afternoon, for about three hours, the sun burst through. Then the sky went back to sulking and then out and out sobbing.

And one patch where we were picking went nuts. I picked a bunch of Agaricus - all red-brown topped, all looking exactly the same in the woods... almost. Even in the woods, I could see differences in the stipes, in the color of the gills (some were more peachy, some salmon, some grayish in the young caps), and a lot of difference in the depth of brown scales and the pattern of red undertones on the cap. Skirts were different too.

I knew I had at least three, maybe more varieties here.

When I got home I started examining them trying to classify them. Trying to even GROUP them. Some stained red under the gills, some stained barely red or barely yellow on the stipe, some smelled briefly of phenol then of savory anise or even fruit. No almonds... But all kinds of differences.

I eventually gave up, and just classified them as edible or not. Only a few were tossed as potentially inedible (phenol smell stuck around too long). The rest were either dried or eaten for dinner. No subsequent effects.

I wondered what was going on in those woods! Just a small patch of woods, maybe 2 acres, with so many different varieties of reddish brown topped Agaricus! But so MANY variations, and NO WAY to key any of them - none of them keyed more than 90% to anything, and something was always wrong to key them 100%.

A week later, the solution was provided. Back at that hemlock tree where we saw the first woods Agaricus - Again we find, right on the dripline of that old hemlock, exactly in the same position as those first mushrooms, more Placomyces. But it no longer keys as Placomyces!

This time something is different.

Beside the Placomyces were five small Agaricus mushrooms. Very small button mushrooms that unfurl into about 5 cm caps. Very reddish caps. Stems and caps that smell deliciously of almonds. These key out to Agaricus tennuiannulatus.

It has been a while since I picked and examined the Placomyces, and the colors seem different today (more reddish and brown to the cap, though the overlying coloration is still distinctly black and not brown). So I pick one and break the stem. And sniff the stem. This is a phenolic mushroom... and it now smells of almonds! Placomyces that smells of almonds!

There are two more of the Placomyces, one about 2 ft further away from the smaller almond agaricus mushrooms, which is HALF reddish on the cap, half not, and smells equally of almond and phenol. And further away still, a classic Placomyces which has no red to it, and smells strictly of phenol.

The logical conclusion is that the nearby smaller Agaricus mushrooms are affecting the Placomyces. In fact, the closer the Placomyces are to the Mystery Agaricus, the more they smell like almonds.

If we extrapolate in logical directions from here, it is reasonable to suppose that many (if not all) Agaricus species are capable of hybridizing. So the woods may be full of mushrooms that look identical, but which are in fact NOT the same species, just variations on several intermingled species. This would account for the inability of anyone to find an exact match for most Agaricus, for the varied descriptions, and for the wide variety of mushrooms within a relatively small ecosystem which look identical on the surface but which are, in fact, all very different.

The woods in which we hunt mushrooms ARE sort of special, in that they are a haven for wildlife, which come from miles around for water, meaning that there is a higher than average distribution of spores from animal dung. But they aren't THAT special, and if it is happening in those woods, it is happening in other woods too. This is just a slightly concentrated example of what is happening elsewhere on a much more distributed scale.

The examples in those woods has lead me to conclude that much of the time, trying to key a brown, white, or gray Agaricus is likely to be futile unless there is a distinctive feature such as the absorbing veil of the Meadow Mushroom, or the large size and distinctive smell of the Prince (who is a much mis-identified mushroom also). (Wow... the last half of that last sentence could have been lifted from a bad Historical Romance!)

The trick is to determine EDIBILITY. And that is pretty easy! Forget trying to tell exactly what long and unpronounceable Latinized name to attach to the fungus in front of you. Just smell it and figure out if it is edible or not. Once you know that, you know as much as anyone would know if they DID identify it!

But... and this is IMPORTANT!

MAKE SURE YOU DO AN EDIBILITY CHECK ON EVERY AGARICUS MUSHROOM YOU PICK!

Do not assume, that just because they were growing side by side, that they are the same mushroom! Do not assume that all of them in the grove you just raided are either poisonous or edible! We have found yellow staining phenolic brown capped Agaricus growing right next to red staining savory anise scented brown capped Agaricus mushrooms, with non-aromatic non-staining brown capped ones scattered in between! Our basket may be full when we come home, but EVERY SINGLE MUSHROOM has to be examined and screened before it goes either in the pot, on the drying screens, or in the garbage.

Personally, I am not crazy about the flavor of Agaricus mushrooms. They all seem to end up tasting just like white buttons when they are cooked. Very mushroomy, brownly fungusy. And I have never particularly enjoyed that flavor, and have never AT ALL enjoyed the texture of mushrooms (nasty slug things). But I hide them in my food anyway, because I need the health benefits of mushrooms. Agaricus are easy to hide, and once you know the key to safety, they are a relatively safe wild mushroom to hunt and consume.

I am far from an expert on either mushrooms, or nature, and certainly not an expert on Agaricus mushrooms (I kind of doubt there is any such thing). The rules for edibility are the ones I use which have stood me in good stead, and never made me sick (or anyone else eating at my table).

But I still advise you to take what I say cautiously. Get a few more opinions before you decide to take my rule and adopt it as your own.