lace lichen

Ramalina menziesii, the lace lichen or fishnet, is a pale yellowish-green to grayish-green fruticose lichen. It grows up to a meter long, hanging from bark and twigs in a distinctive net-like or lace-like pattern that is unlike any other lichen in North America. It becomes a deeper green when wet. Apothecia are lecanorine. Lace lichen is an important food source for deer in the Coast Range of California, and a source of nest material for birds. It is highly variable in its growth form, with branches sometimes so slender as to appear like strands, sometimes tiny, and sometimes large with broadly flattened branches.

Excerpt from the Wikipedia article Ramalina menziesii, by its authors, under the CC BY-SA 4.0 licence.