A Sessile Earthstar (Geastrum saccatum) found growing beneath Western Red Cedar. When Earthstars first emerge from the soil, they have a slightly pointed, onion shape. The skin, or peridium which covers the Earthstar is comprised of three layers, two outer and an inner layer which encapsulates its spore bearing cavity. When the Earthstar gets wet, the outer two layers split open to form 4-8 rays. As the pedals open, leaves are pushed aside, and the spore filled sack rises above the leaf litter. When rain drops hit the enclosed inner layer, it causes the Earthstar to puff out its spores. Elijah Bristow State Park, Willamette Valley, Oregon.