SONOMA COUNTY, CALIFORNIA
These might look like ice formations, but they are actually a type of slime mould (Ceratiomyxa fruticulosa). They’re also tiny, with each branch measuring just a couple of millimetres in length.
This slime mould can be found growing all over the world, typically covering decaying wood like a layer of frost. But ice isn’t the only thing it can be mistaken for, because slime moulds used to be classified as fungi. You can see why – they grow on rotting plant material, they release spores to reproduce, they even have mould in their name. But slime moulds are actually classified as protists, and there are at least 1,000 known species.
The branches you can see here are part of the mould’s reproduction process. Spores form on tiny stalks that cover the upper portion of each branch, before being released to start a new patch elsewhere.