Common Woodchip Fungi of the Bay Area (East)

 

For the greater part of the year, the San Francisco Bay Area features sunny, but cool and dry climate. From May to November rains are particularly unusual and outside of the watered areas in the local parks, mushrooms are rare. All this changes with the onset of winter when the Pacific Ocean unleashes its storms with a fury. Having gained moisture over the vast expanse of the ocean these systems are wet and travel far. By the time the TV News report on floods and deep snow in the rest of the country along their path, we should head for the woodchip patches to see who has awakened after the long dormant summer.
 

The woodchip covered surfaces in the urbanized zones present a readily accessible laboratory of fungal development. It is a great way to initiate beginners without the need to travel too far. While not the preferred ground for mycophiles, those who enjoy the mere sight of fungi in great numbers, and like to learn more about them find the woodchip patches most convenient.

 

The broader Bay Area is a fairly large territory that features several unique microclimates and habitats. This write-up addresses the rectangular area on the map (marked with pink) where I do most of my woodchip exploration.

 

The variety of park and garden mushrooms is great, including many ectomycorrhizal species. Distinguishing which species prefer woodchips versus the surrounding non-woodchip areas requires repeated observation and judgment. Here I have included only the species that I have seen at least 3 times. Excluded are common grass species, such as Conocybe lactea, Panaeolus phoenisecii and many others.


The San Francisco Bay Area


In general I am not equipped to always be able to identify the type of woodchip material, but since I have personally observed how the park service tends to mulch whatever is left from tree management, in many cases one can easily surmise its origin. In general, the woodchips in the East Bay fall in the following 3 groups of origin:

 

Monterey Cypress     (Cupressus macrocarpa)

Blue Gum                   (Eucalyptus globulus)

Pines                          ("Monterey"  P. radiata, "Torrey"  P. torreyana,  "Aleppo"  P. halepensis, and various others)

 

The Monterey Cypress is a California native tree that has spread outside of its natural habitat into most parks. Other European Cypresses have also been widely planted.  The fast growing, Blue Gum tree (Eucalyptus globulus) has become the most abundant tree in the urbanized areas. It was introduced in the late 19-th Century from Tasmania and has found the local conditions very favorable. On the other hand, it is not favored by mycophiles, as it is not particularly friendly to mushrooms, and even less so to mycorhizal species. The most common pines in the local parks are Monterey Pine (Pinus radiata) and Torrey Pine (Pinus torreyana). Other Western pines are planted too, as well as many other introduced pines, such as Aleppo Pine (Pinus halepensis).

 

Following are the most common woodchip species, ordered by frequency of encounter and size of patches (subjectively).

 

Stropharia "riparia"

 

Commonly known as the "Highway Stropharia" -- this species is probably unnamed. S. percevalii looks very similar, but has much larger spores. The original S. riparia that A.H. Smith described from the Pacific Northwest is significantly smaller in size although that microscopically I have not been able to detect differences. This is  the most abundant species by far in this kind of habitat. In the woodchip covered divider of a local highway, I have seen patches stretching for miles during the rainy spells. Once finding myself overpowered by an outburst of McIlvainian spirit I sautéed a few caps and found it to be an excellent edible.

 

Stropharia riparia

S. riparia & S. aurantiaca

Stropharia aurantiaca

 

This mushroom of an unknown origin has become known worldwide.  It is easily distinguished from a distance, bragging powerfully contrasting, yet beautifully harmonized colors. Its beauty can best be appreciated under gloomy skies on a rainy day.

 

 

Stropharia aurantiaca

S. riparia & S. aurantiaca

Agrocybe praecox

 

This is another "in your face" mushroom that pops up anywhere on or close to woodchips. It also claims worldwide distribution. But unlike the previous two species, I have seen it quite frequently outside of woodchip areas -- clustered in leaf litter, on the side of roads, or in pure Oak stands. Its cracked pileus is quite distinguishing in most cases, although when young it can look very similar in stature to S. riparia.

 

Agrocybe praecox

Stropharia ambigua

 

This gorgeous native of the Pacific Northwest graces many quarters in its natural habitat, but by far the most magnificent patches that I have seen locally were on Eucalyptus mulch. Substantial in size and purportedly benign, it's strong earthy odor ("dry leaves" according to Arora) makes it quite unappealing to be tried in the kitchen.

Stropharia ambigua

 

Tubaria furfuracea

 

This quintessential little brown mushroom (LBM) would be perfectly ignorable if it weren't for the immense troop numbers when it decides to fruit. Recently I inspected several collections to determine whether they really represent 'furfuracea' and it turned out that they do indeed

 


Tubaria furfuracea
Agrocybe putaminum

Gymnopus "stinkii"

 

This commonly seen fetid species forms dense clusters on well rotted woody material. Curiously, according to Prof. Desjardin it still remains formally unpublished. It has a sister taxon from the Eastern NA that shares the same faith. Macroscopically, it looks similar to Gymnopus brassicolens from Europe.

Gymnopus sp. (undescribed)

Pluteus cervinus

 

Woodchips or not, wherever something is rotting, it seems that the Deer mushrooms has found its home. P. cervinus is by far the most common representative of the genus in the woodchip beds. I think I have seen P. atromarginatus and probably others, but the taxonomy of this genus for California hasn’t been fully developed yet and a dedicated local monograph is not available. Therefore, I am shying away from doing the research to put better names to the species that I encounter.

Pluteus cervinus

Hypholoma fasciculare

 

This cosmopolitan fungi with a worldwide distribution is quite common in nature near decaying wood, as well as being abundant on pine mulch. It is readily distinguished by the greenish colors of its gills in maturity as well as by its bitter taste. Unfortunately, its sought after cousin, H. capnoides, is far rarer in my experience.

 

Hypholoma fasciculare

Peziza repanda

 

A very common ascomycete on woodchips of all origins. It is a member of a confusing group that requires microscopical analysis to be identified precisely.

Peziza repanda

Gymnopilus sapineus

 

The bright orange/yellow clusters of this mushroom can liven up the view on gray days. As common as Gymnopilus spp. are in their natural habitat in the early part of the mushroom season, in the local parks G. sapineus comes later and after the extended rainy spells have soaked the pine mulch quite well.

 

Gymnopilus sapineus (both pictures)

Volvariella speciosa

 

This is the only species in this genus that is officially recognized from California. An abundant species, it is as common to find on woodchips as it is on lawns. V. speciosa is the only mushroom I have seen fruiting consistently amidst the locally widespread "Ice plant" (native of S. Africa).

 

Volvariella speciosa (can get quite large) 

Clathrus ruber

This is one of the most striking mushrooms. Its beauty is matched only by its stinky odor. Tropical species by origin, it has been spreading rapidly throughout the woodchip beds in the area. From published reports, it seems that its expansionist march is not limited to California only.

Clathrus ruber (gorgeous Stinkhorn)

Psathyrella candolleana

Known as a typical park mushroom, I see extensive growth on woodchips that are in an advanced stage of decay.

Psathyrella candolleana

Coprinus leiocephalus

 

This fragile little inky cap is most likely to be mistaken for C. plicatilis, which is a close relative. Early in the season, after the first heavy rains, I've seen densely populated patches that amount to several hundred, even thousands of fruitbodies.

Coprinus leiocephalus

Psathyrella conopilus

 

Forming beautiful troops in older woodchip patches mixed with grass, this frequent and slender specimen can be identifies microscopically quite easily due its pileus features – long setae reaching 200μ in length. Supposedly they can be seen with a hand lens, but my attempts were not entirely convincing.

 

Psathyrella conopilus

Tapinella panuoides (=Paxillus panuoides)

 

I have included this species here because two years ago it was quite frequent on pine mulch. I am yet to see it this season (it has been dry overall).

Tapinella panuoides

Lysurus mokusin

 

Occasionally, I see Lysurus mokusin popping up later in the season, after the first extended warm spells of the Spring.

Lysurus mokusin

Chlorophyllum brunneum

(=Macrolepiota rachodes)

 

While not strictly woodchip species, it bears mentioning that whenever Cypress mulch is laid thick this species demonstrates an explosive growth, forming thick clusters.  

 

 

There are a couple of areas in the East Bay where we regularly collect a few pounds of shaggy parasols per visit. Best fruiting is after the first warming trend of the Spring.  Undercooked it can cause a mild gastrointestinal upset (experienced by me). Otherwise it is a splendid mushroom that can be used in various recipes.