Mushroom Monday
Winter polypore (Lentinus brumalis)
Good evening, friends,
With acknowledgement that it was 60 and sunny yesterday, and that I did indeed break out the shorts and sandals, we’re still not quite out of the woods yet. The calendar still says it’s winter and today we’ll look at the Winter Polypore (Lentinus brumalis) which I found this past Wednesday at Manitou. We don’t often get fresh, fleshy fungi this time of year and this species in particular, as we’ll learn, is out of this world.
Fun Facts
DNA sequencing recently reclassified the fungus from Polyporus brumalis to Lentinus brumalis. Other members of the genus Lentinus, like the Tiger Sawgill (Lentinus tigrinis) or your household Shiitake (before it was placed in Lentinula), are gilled mushrooms. Yet L. brumalis - like other polypores - has pores. It is thought that gills (which have an increased surface area relative to pores) evolved independently in certain fungal lineages as a more advantageous method of spore dispersal.
In the 1970s, the Soviets blasted L. brumalis cultures into space to understand the effects that light and gravity had on the formation of these mushrooms (References 3 and 4). At that point in time it was understood that the mushrooms were negatively geotropic (grew opposite the pull of gravity) and also phototropic in that the fungus grew directionally toward light.
One study had the mushrooms grow in test tubes while in orbit. The researchers noticed that the mushrooms would grow relatively normally in orbit when exposed to light, and if the tubes were flipped over the mushrooms would begin to reorient themselves against the pull of gravity. The mushrooms maintained their negative geotropism and phototropism in space.
However, mushrooms that were kept completely in the dark did not grow at all, or if they did they would produce stipes (stems) but neither a cap nor pore surface. Mushrooms that were grown in the dark and in the absence of gravity would grow into the shape of a corkscrew or a ball. The researchers tried a variety of different light and gravitational conditions - they we’re having fun up there - to determine the formation of the mushroom has a strong dependence on “space orientation, gravity and light” (Reference 4).
The etymology of Lentinus is derived from the Latin lentus which means “clinging” and “tough” and refers to the durable, rubbery texture of the mushrooms. The species epithet brumalis comes from the adjective “brumal” which means “indicative of or occurring in the winter” and refers to the time of year we find these polypores.
Ecology
L. brumalis is saprobic and digests the dead wood of deciduous trees (especially birch, where our specimen was found). The mushrooms aren’t big, the caps don’t grow much larger than three inches across and the length of the stipe (stem) is usually half the diameter of the cap. The fungus can be found throughout temperate forests of the northern hemisphere and pops up fall through spring.
There is a sister species, the Spring Polypore (Lentinus arcularius) which is pretty difficult to distinguish from L. brumalis. L. arcularius is pretty hairy at the margin of the cap and, in fact, you can see hairs at the cap margin in the photo above. However, the cap is also supposed to be lighter in color, the pores of L. arcularius are larger and run down the stipe, and the mushrooms are generally smaller than L. brumalis.
There are yet other look-a-likes. Another sister species, the Fringed Polypore (Lentinus substrictus) has even less known about it but is also apparently quite hairy at the margin of the cap. The Blackfoot Polypore (Cerioporus leptocephalus) and the Hexagonal-pored Polypore (Neofavolus alveolaris) both look similar but the former is black at the point of attachment to the wood and the latter has a lighter cap and larger pores than our L. brumalis.
Looking Forward
A couple fun things in the works right now. I’m taking over the New York Mycological Society instagram account this week. You can follow along here.
Next weekend Mushroom Monday is going to Boston for a special project which will be debuted at a later date. Later in the month, I’m going to Ecuador to look for mushrooms with renowned mycologists Alan Rockefeller and Mandie Quark in the Amazon. Lots to get excited about.
Today’s the one year anniversary of when I made the move to substack and readership has nearly doubled since then. Whether you subscribed today, or have been here for the long-haul, thank you for reading.
Daylight savings this weekend and then it’ll really feel like spring,
Aubrey
Bonus Beaver Picture
I also plan on publishing the second part of the inquiry into beavers for the premium subscribers later this week.
References
Kuo, M. (2015, May). Polyporus brumalis. Retrieved from the MushroomExpert.Com Web site: http://www.mushroomexpert.com/polyporus_brumalis.html
https://www.messiah.edu/Oakes/fungi_on_wood/poroid%20fungi/species%20pages/Lentinus%20brumalis.htm
Kasatkina TB, Zharikova GG, Rubin AB, Palmbakh LR, Vaulina EN, Mashinsky AL. Development of higher fungi under weightlessness. Life Sci Space Res. 1980;18:205-11. doi: 10.1016/b978-0-08-024436-5.50028-7. PMID: 11971286.
Zharikova GG, Rubin AB, Nemchinov AV. Effects of weightlessness, space orientation and light on geotropism and the formation of fruit bodies in higher fungi. Life Sci Space Res. 1977;15:291-4. PMID: 11962503.
https://www.inaturalist.org/taxa/947949-Lentinus-brumalis#cite_note-18
Kuo, M. (2015, March). Polyporus arcularius. Retrieved from the MushroomExpert.Com Web site: http://www.mushroomexpert.com/polyporus_arcularius.html