Bloodfern

This blood red or dark grey moss is commonly found growing in medium-sized clumps On rotten logs, In heathlands, and In bogs.
It is small, growing up to 1 inch (3 cm) tall. It forms in extensive patches and they spread and grow quickly, and is extremely tough; it can easily endure being trodden on.
When mature, emerald flame-shaped capsules grow at the end of elongated, lime green sporophytes, eventually opening up during the early winter to release thousands of spores; it can cause allergic reactions.