Sime Mold Time Lapse and More

Sometimes a developing slime mold can make a fun short-term pet. If you collect them early enough, you can watch them change over time. It's a tricky endeavor, as the developing sporangia are incredibly delicate, and squish with the gentlest of touches. Also, I'm rather clumsy. Usually I enlist my coordinated husband to carefully cut a small sample from the rotting log or other substrate. Then, I have to try to carry it through the rest of the hike and home without letting my field bag bob around too much or turn upside down. I've gotten more successful with practice. (Slime mold plasmodia can also make fun, longer-term pets. They are easier to collect, and will sometimes live for months. I haven't had one in a while; when I next bring one home I'll be sure to post about it!)

Here's a young Hemitrichia (maybe H. calyculata?) that I managed to bring home safely recently. The first photo was taken in the field (Seward Park, Seattle), and the rest were at home. I only brought home a small sample, and left plenty in the field to develop and release spores back into the wild! The sporangia are tiny -  only about 2 mm tall. A lot of slime mold sporangia are white early on in development, which makes them easier to spot. Over the next few days the sporangia turned lavender-grey (I didn't get a photo of that, sorry), then orange-brown, dark brown, and finally their final ochre color.

Sept. 15, 8:00 am

Sept. 16, 7:00 am

Sept. 17, 7:00 am

Sept. 17, 4:00 pm

I wasn't able to get these Hemitrichia to pop. A white fungal mold started to grow on the wood substrate, and I think I let them dry out too soon, trying to halt the mold's progress. When I manage the humidity better, the top will pop off the sporangia, which is full of spores and little hairs called capillitium. As the hairs are released, they fling the spores out into the world. Here's a Hemitrichia I collected a couple of years ago with the top popped.

Fully developed punk rock Hemitrichia

The more I learn about slime molds, the less confident I am with my identification, in part because the appearance can change so much during development. My reference books usually only describe the end state. It's always fun to bring one home as a pet and see what it turns out to be. (Identification can still be challenging, though, as it sometimes hinges on microscopic details of the spores or capillitium.)

Closer to home in Dead Horse Canyon (Lakeridge Park, Seattle) I found my first ever Cribraria canecellata! It was already fully developed, so I don't have a time lapse of it, but it is too beautiful not to include here. The spores are encased by a delicate cage-like structure called a peridial net.

Cribraria cancellata

Cribraria cancellata, peridial net

Cribraria cancellata, peridial net

Hooray for the sporadic rains of autumn, bringing nature treasures like slime molds, oak galls, and mushrooms! More about oak galls and mushrooms soon!