Edible Mushrooms in my Worm Bin

Every single time Bagasse Mushrooms appear in my compost I am amazed. Mainly because these mushrooms are considered to be gourmet edible mushrooms, fetching high prices at markets worldwide, yet they have decided to volunteer in no less than 3 of my compost systems! Before these mushrooms, aka Paddy Straw Mushrooms (Volvariella volvacea), began appearing in my compost, I had never intentionally cultivated them; I have never introduced their spawn nor their spores to the land that I am stewarding. I have never even bought this species of mushroom from the market; so no parts of this species – neither tissue nor spores – have ever intentionally ended up in my compost after having been on my kitchen’s cutting board! And yet they have found their way to my compost systems. I suspect the wind has brought in their spores.

Bagasse Mushroom growing in a raised bed keyhole composting chute under fruiting tomato plants by Chase | Tropical Fungi Academy


Different mushroom species frequently pop up in my compost, most commonly different varieties of Inky Caps. Yet this mushroom species, no doubt due to its size, always elicits the “WOW factor” from myself & my roommates. Speaking of roommates, I can’t help but wonder if they are slicing-&-dicing Bagasse Mushrooms in the kitchen behind my back & surreptitiously sneaking pieces into our compost pails (they insist they are not though).

Bagasse Mushroom growing in compost tumbler by Chase | Tropical Fungi Academy


The Bagasse Mushroom is a hot weather loving mushroom that is widely cultivated in the tropics. Due to its extremely short shelf life, fresh specimens can only be purchased in locations very close to where they are grown. Most people around the world who eat these mushrooms get them preserved in tin cans labeled “Straw Mushrooms” from grocery stores. They are most typically eaten in soups & stir fries & are prized for their delightful aroma & umami flavor.

Bagasse Mushrooms growing in worm compost bin. Note the compost worm crawling in between them! By Chase | Tropical Fungi Academy


Distinguishing features of Bagasse Mushrooms are their compost habitat, a prominent & thick, sack-like egg at the base of the stipe, lack of a ring or skirt on the stipe, & pinkish brown to salmon-colored spores (as seen on the spore-dusted on the caps in the photo above).

Properly identifying mushrooms takes a few steps. Oftentimes it is difficult – if not impossible – to identify a mushroom just by looking at its top surface alone.

It is critical to also look underneath the mushroom to see what kind of fertile surface type it has. Different species of fungi can sometimes look very similar from above, but actually have vastly different kinds of fertile surfaces below. For example, with the classic cap-and-stem mushroom the fertile surface is located on the bottom side of the cap. There you will see the fertile surface on which the mushrooms spore’s (like plant seeds) are formed.

There are 3 different shapes of fertile surface types that you will most often find under the cap:

  1. Gills look like pages in a book.
  2. Pores look like a bunch of small – sometimes very tiny – holes.
  3. Teeth look like elongated, cone-shaped spines.
    […and some mushrooms have veins underneath.]

hymenophore types

Sometimes when identifying, we only want to know what type of fertile surface a mushroom has. To do this we actually do not need to pick it from the earth – or maybe the the mushroom doesn’t want to be picked! Perhaps it is still too young & we want it to complete its lifecycle by maturing & releasing its spores yet we still want to know what kind of mushroom it is. In this case, we can use a dental mirror to see what kind of fertile surface the mushroom has to help us with identification.

It’s easy. What we do is simply hold the dental mirror against the ground underneath the mushroom’s cap, & then angle the mirror towards our eyes so that we can see if the mushroom has gills, pores, or teeth. This step can either get us closer to identifying a mushroom to species or can sometimes even give us a definitive answer as to what the mushroom is.

Photo by Jason Youth | CC0 public domain | iNaturalist

Photo by Jason Youth | CC0 public domain | iNaturalist

Always be sure to see what kind of fertile surface the mushroom has. And if getting help from others by sending them your photographs of the mushroom, be sure to always include a photo of the fertile surface in addition to the top surface.

If you want to learn more about mushroom ID, then please join us for our next mushroom identification class by clicking here.

Mustard Yellow Polypore

One will stumble on Mustard Yellow Polypores (Phellinus gilvus) outdoors nearly anywhere there is dead wood. This fungus is everywhere, even possibly at the site of our next workshop. It is also known to be supremely medicinal and has been shown to have antioxidant, antimicrobial, anti-cancer, and wound healing properties [see references below].

I was excited to stumble upon log after log full of these mushrooms recently & ended up spending way too much time photographing them. This is how you identify them (I have de-coded the technical words from the identification literature into common language & left the technical words in parenthesis).

One can find Mustard Yellow Polypores growing out of dead logs laying on the ground or on standing, dead trees. They can grow as an individual conk, in groups (gregarious), or in a cluster of overlapping shelves (imbricate). Mustard Yellow Polypores form half moon-shaped (semicircular) shelves with a relatively flat (applanate) surface or they can be slightly convex.

The top surface of this fungus is dark yellowish brown with a mustard-yellow (tawny-olive) colored outer edge (margin) at young and middle age. The whole fungus turns dark brown in old age. Older individuals tend to have concentric (zonate) furrows which are of the same color (concolorous). Mustard Yellow Polypores can appear to have an irregularly lumpy and wrinkled (rugose) surface which is velvety (velutinous) at younger stages & becomes bald (glabrous) when older.

This fungus is broadly attached to the host, therefore it has no stipe (sessile).

Mustard Yellow Polypore pores

Pores on the spore-bearing surface

Underneath, Mustard Yellow Polypores have pores that appear purplish, light brown (ochre) to purplish brown. The round pores are very small and occur 6-8 per millimeter.

The next time you see this mushroom growing, say hello! 🙂


Antioxidant and Antimicrobial Activities of Fruiting Bodies of Phellinus gilvus Collected in Korea. Ki-Nam Yoon, Hyung Seok Jang. Korean J Clin Lab Sci. 2016;48(4):355-364. https://doi.org/10.15324/kjcls.2016.48.4.355 pISSN 1738-3544 eISSN 2288-1662.

Inhibitory effects of polysaccharides isolated from Phellinus gilvus on benzo(a)pyrene-induced forestomach carcinogenesis in mice. Jae-Sung Bae, Kwang-Ho Jang, Hyunee Yim, Seung-Chun Park, Hee-Kyung Jin. World J Gastroenterol 2005;11(4):577-579. World Journal of Gastroenterology ISSN 1007-9327.

Polysaccharides isolated from Phellinus gilvus enhances dermal wound healing in streptozotocin-induced diabetic rats. Jae-Sung Bae, Kwang-Ho Jang, Hee-Kyung Jin. College of Veterinary Medicine, Kyungpook National University, Daegu 702-701, Korea. J. Vet. Sci. (2005), 6(2), 161–164.

Polysaccharides isolated from Phellinus gilvus inhibit melanoma growth in mice. Jae-sung Bae, Kwang-ho Jang, Hyunee Yim, Hee-kyung Jin. Department of Surgery, College of Veterinary Medicine, Kyungpook National University, Daegu 702-701, South Korea. Department of Pathology, Ajou University School of Medicine, Suwon, South Korea. Department of Laboratory Animal Medicine, College of Veterinary Medicine, Kyungpook National University, Daegu 702-701, South Korea. Received 21 June 2004; received in revised form 31 July 2004; accepted 2 August 2004.

Whole-genome sequence of Phellinus gilvus (mulberry Sanghuang) reveals its unique medicinal values. Jinxi Huo, Shi Zhong, Xin Du, Yinglong Cao, Wenqiong Wang, Yuqing Sun, Yu Tian, Jianxun Zhu, Jine Chen, Lijiang Xuan, Chongming Wu, Yougui Li. Journal of Advanced Research 24 (2020) 325–335.

I’m so excited that the recent rains have brought out the turkey tail mushrooms. I love that when I happen upon these mushrooms they are nearly always fruiting in great abundance. And yes, they do really look like turkey tails, or as the Dutch say, fairy benches (elfenbankje)!

If you are curious about identifying this mushroom yourself, this is an easier one that is good for beginner fungi enthusiasts. One can easily tell when they are looking at turkey tails by observing that they are:

  • occurring in groups of overlapping clusters & rosettes on fallen wood,
  • half-moon / fan-shaped,
  • broadly attached to the wood (sessile),
  • thin & leathery,
  • feature concentric zones that vary in color from brownish, to buff to various shades of gray & which also vary in texture from matted-wooly to shaggy,
  • and finally, turkey tails have cream-colored pores underneath that are easily visible.

Turkey Tail Mushrooms

Turkey Tail Mushrooms

Turkey Tail pores

Turkey Tail pores

The closest look-alike fungus I most often see around my parts are Microporus mushrooms. These fungi often, but not always, grow either singly or scattered a few inches away from one another. Also, the pores of Microporus are much smaller & very difficult to see with the naked eye. Finally, they have a dark stipe (“stem”), unlike a turkey tail mushroom which lacks a stipe.

Tinypore Mushrooms

Tinypore (Microporus sp.) Mushrooms

Tinypore hymenophore

Tinypore (Microporus sp.) hymenophore

If you would like to learn more about mushroom identification, be sure to click on this link to check out our latest educational offerings.