Emerald

This drab green moss is commonly found growing in large clumps On trees, and In damp forests.
It is short, growing up to 2 inches (5 cm) tall. It forms in extensive patches and they overwhelm an area rapidly, and is slightly delicate; it takes a lot of damage when trodden on.
When mature, emerald V-shaped capsules grow at the end of elongated, lime green sporophytes, eventually opening up during the mid-autumn to release dozens of spores; it can cause severe allergic reactions.