Emerald

This gray moss is commonly found growing in giant clumps In marshes, and On trees.
It is small, growing up to 1 inch (3 cm) tall. It forms in extensive patches and they overwhelm an area rapidly, and is extremely strong.
When mature, emerald heart-shaped capsules grow at the end of long, lime green sporophytes, eventually opening up during the mid-summer to release thousands of spores.