large patch of short (<1cm) fruiting bodies on Populus sp snag
This photo shows the slime mold as well as the plasmodium (white blobs) which will become the next fruiting. Though the slime mold appears reddish, it will become chocolate brown.
immature state here: http://www.inaturalist.org/observations/315999
yellow; mature state here: http://www.inaturalist.org/observations/322061
Working with students when one of them came across this. I was unfamiliar with it so we looked it up!
This fungus ejected spores when poked with a twig and dangled off a rotten log in a similar fashion to Goat's Beard.
Stemonitis is a distinctive genus of slime moulds found throughout the world (except Antarctica). They are characterised by the tall brown sporangia, supported on slender stalks, which grow in clusters on rotting wood. Identification within the genus is difficult, and can only be performed with confidence using a microscope.