September Salt Spring Island Fungus of the Month: Strobilurus trullisatus

Douglas fir trees follow a 5-7 year cycle that affects how many cones are produced. One year each cycle,  the "mast year", all the trees make an extra-large crop of seed cones, sometimes thousands on a large tree. Other years have smaller crops, or sometimes almost no cones at all. 2019 was a very sparse year for Douglas firs across the island, but this year there are a LOT more cones. 

We aren't entirely sure why some tree species follow an irregular mast cycle. It might help keep the population of seed eating animals low, or the trees may be responding to weather cues. Whatever the reason, there will be an extra-thick layer of fallen cones on the forest floor this year. 

observation by corvi

As they age, the fallen cone mast will be colonized by the Fir Cone Mushroom, Strobilurus trullisatus. This small mushroom has a white cap and a yellow stem, and breaks down old Douglas Fir cones. It is the most common cone-decaying mushroom on the island. 

observation by spinyurchin

All fungi in the Strobilurus genus decay fallen cones, but Strobilurus trullisatus is found only on Douglas Fir cones. Sometimes it may seem to sprout from the ground is the cone is buried. Luckily, we'll have lots of cones! 

Posted on 28 de novembro de 2020, 05:07 AM by corvi