Common or rock polypody, American wall fern, rockcap fern
Polypodium virginianum

a small stand on the Cabin John trail

This little fern is no less charming for being incredibly common.  It’s found throughout most of the eastern US and Canada except for parts of the deep south.  Although short (the fronds are usually about twelve inches long), the rhizomes will form massive colonies in suitable habitat, which consists of all sorts of rock outcroppings and rocky soils in moist shade.

an itty-bitty specimen at Carderock; it doesn’t have much soil to grow in!

 
It’s also an easy fern to identify, especially at this time of year, since it’s evergreen.

new fronds in late April along the Cabin John trail