About Polystichum scopulinum (D.C.Eaton) Maxon
Polystichum scopulinum (D.C.Eaton) Maxon is a species of fern that goes by the common names mountain hollyfern and rock sword fern. It is native to most of western North America, and also has known disjunct populations in eastern Canada. This fern grows in rocky habitat, and is often found growing in full sun. It is widespread, but occurs mostly in small populations, and it has been noted to be most abundant on serpentine soils. This fern grows several erect, narrowly lance-shaped leaves that can reach up to 50 centimeters in length. The leaves become narrower toward their bases. Each leaf is divided into many lance-shaped or oblong leaflets that grow up to 3 centimeters long. The toothed leaflets are sometimes twisted along their axes and overlapping. P. scopulinum is thought to be a fertile allotetraploid that has Polystichum munitum as one of its parent species.
