How to recognize apple moss: Bartramia pomiformis is most easily spotted when it has its round green capsules held above the cushion of plants. These capsules are apple green and round when they first grow. Later on when dried out and empty of spores, they become brown and furrowed and more elongate. The plants grow upright and form low light green cushions on rock faces and ledges. The 4-6 mm leaves are long and narrow with a sheathing base and a midrib and teeth along the upper part of the leaf. When the plant is moist these leaves are straight and stick out from the reddish stem, but they curl and twist when dry. There are many reddish rhizoids (filaments of long cells) which looks like fuzz along the base of the stems. These rhizoids help to hold it in place in the harsh environment where it grows. Microscopic features of interest are the doubly toothed bistratose leaf margins, and the papillae (little bumps) found on the upper leaf cells. These papillae make the leaves look dull.
Where to find apple moss: Bartramia pomiformis prefers shaded rock outcrops or cracks; the rocks are usually acid but the apple moss also grows on calcium enriched rocks. Ravines and soil banks also occasionally provide a home for this plant.