Embermoss

This pink-red moss is commonly found growing in tiny clumps On rotten logs.
It is short, growing up to 2 inches (5 cm) tall. It forms in sparse patches and they overwhelm an area rapidly, and is slightly hardy; it can easily endure flooding and draughts.
When mature, emerald flame-shaped capsules grow at the end of elongated, lime green sporophytes, eventually opening up during the late summer to release millions of spores; it can cause severe allergic reactions.