Latin name: Pluteus cervinus, Pluteus petasatus, Pluteus exilis and related species
Common names: Deer mushroom, deer shield mushroom, fawn mushroom
Season: Spring, summer, fall (late fall in the southern states)
Edible: Yes
Flavor: Acceptable
Medicinal: No
Nutritional: Unknown, most likely similar to other mushrooms
Identification difficulty: Novice
The deer mushroom is the largest and most commonly encountered member of the genus Pluteus. It's encountered frequently in both North America and Europe, probably contributing to its rather long history, as this mushroom was first documented in 1774.
The common names actually indicate one of the key types of identification of this mushroom, the tendency of the cap to shimmer with subtle reflectivity, similar to the silky sheen of a fawn's coat. But more on that in the identification section.
Warning: This is NOT an easy mushroom to identify, and there are a fair number of dangerously poisonous and even deadly mushrooms that look similar. Close inspection to gill attachment is required for safe identification. Spore color is an important identification aspect of these mushrooms, so I recommend that if you are inexperienced with this mushroom, you wait until the gills turn pink OR do a spore print before consuming.
A note on Pluteus species
The mushrooms we call "deer mushrooms" and historically identified as "Pluteus cervinus" are actually 3 or more distinct species of the Pluteus genus, including Pluteus exilis and Pluteus petasatus. There might actually be more species that are still yet to be identified with DNA testing. These mushrooms can't really be distinguished by physical characteristics and must be separated by habitat. More on that below. From a foraging/edibility perspective they can be treated the same.
Identifying deer mushrooms
When and where to find deer mushrooms
Deer mushrooms can be found throughout all states of the continental United States, though they aren't found in the northern halves of the northernmost states. Pluteus cervinus is generally found east of the Rocky Mountains, while Pluteus exilis is found on the west coast. However, Pluteus cervinus has also been reported infrequently in San Francisco, California.
Like all Pluteus species, deer mushrooms grow exclusively on wood. The true "deer mushroom," aka Pluteus cervinus, grows on logs at the bases of dead or dying trees and on stumps. It seems to prefer well-decayed wood and even when growing on trees that are still alive, it will choose to fruit in areas that have lost their bark. The related Pluteus petasatus can also be found in wood chips. Occasionally, you will find deer mushrooms growing on buried wood or roots that seem to just grow from the ground. I recommend avoiding these specimens as it makes it harder to safely identify them.
Deer mushrooms can be found spring, summer and fall, and even into mild winters in the Southern states.
Cap identification features
Deer mushrooms grow rather quickly and top out at large sizes. Caps start out as convex (like an umbrella) but are flat at maturity. Mature caps are 2" to 5.5" in diameter. The mushrooms below grew from the tiny caps on the left to the 4.5" mature caps on the right in just 2 days.
As size is an important identification feature, you might want to avoid specimens with caps smaller than 3" in diameter. Unlike most mushrooms, the young "buttons" don't seem to be superior to mature specimens in either flavor or texture, so you don't miss anything by waiting.
The caps range from medium brown to tan to taupe (greyish) to beige, often with pinkish or pinkish orange undertones. They also generally have an "ubmo" or bump in the middle of the cap. The center is most often darker than the edges, but that can be subtle. The caps also have subtle striations from the middle of the cap to the edges.
When mature, the caps have a lot of shimmer / iridescence as seen in the video clip below. This is especially true if the caps became wet from rain or even just dew and then dried.
Gill & spore features
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| Pink gills at the early stage of maturity. Notice how the gills don't touch the stem. |
When young deer mushrooms have white gills, but they quickly turn a pale pink or a pale peach, then darken to a dusty rose before eventually becoming a tawny taupe with pink undertones. By the time they become that dark they will most likely be buggy though.
I recommend NOT harvesting the mushrooms until the gills are pink, as it's much easier to confuse them with other species when the gills are still white.
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| When slightly more mature gills darken to a dusty rose. These are already a little past prime. |
Officially, deer mushrooms have "pinkish brown" spore prints. Unofficially, there's a broad range of spore print colors for these mushrooms, varying from orange-brown to rusty-brown, to pinkish brown, brownish pink, cinnamon, peachy blush, coppery blush, and various shades of darker Caucasian skin tones.
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| A natural rusty-brown spore print left on one mushroom from the overlapping cap of another. |
The strip below shows some of the colors you might find. If you don't know how to do a spore print, check out my guide here.
The flesh inside the cap is white and doesn't bruise blue or any other color when pressed, cut or otherwise damaged.
Smell
Many people say that deer mushrooms smell faintly of radishes or watermelon rind. I'm afraid I have a terrible sense of smell and rarely smell what other people do. That said, I have picked up on those notes, very, very subtly, exclusively on very fresh specimens. Smell is not an essential identification feature, but I thought it was worth mentioning.
Stem features
Look-a-like species
To rule out potentially dangerous look-a-like species, you should wait for the mushrooms to mature enough that their spores turn pink, perform a spore print and double, triple check that the gills do not attach to the stem. Doing these things will rule out anything potentially dangerous, but we will still break down the look-a-likes below.
Entoloma species - Potentially poisonous
Like deer mushroom, Entoloma species have broad caps, relatively straight, narrow white stems, gills that start out white and turn pink and pink or peach spore prints. In fact, the Enoloma family are often called the "pink gills" as a common name.The most important way to rule out an Entoloma is to check the gill attachment. Entoloma gills will touch the stem; Pluteus are separate from it.
However, Entoloma gills MAY be attached only by a notch, appearing separate at first glance. You must do a thorough inspection of the gills.
The grey knight - Deadly poisonous
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| Photo by user Strobilomyces, curtesy of Wikimedia Commons. Used with permission, view the original here. |
The so-called "Grey Knight" or "Grey Guard" mushroom, Tricoloma terreum, was once considered to be edible but we now know that repeatedly consuming this mushroom can lead to kidney failure and potentially death if life-long dialysis isn't performed or a transplant found.
In overall shape, size and coloration, it can resemble the deer mushroom, having a grey-brown cap, a straight white stem, and white gills. The gills of T. terreum are attached to the stem, but they are attached by a notch, appearing to be separate. While the cap of the grey knight can't get as large as that of the deer mushroom, the largest grey knights will overlap in size with the smallest deer mushrooms.
The best way to rule out the grey knight is by waiting to see if the mushroom's gills turn pink, or by performing a spore print. Tricoloma species have white spores and so their gills will remain white.
