About Polystichum lemmonii Underw.
This fern, Polystichum lemmonii Underw., produces multiple narrow, erect, lance-shaped fronds that range from 10 to 35 centimeters in length. Each frond is composed of many overlapping, folded, and twisted oval leaflets (pinnae), which can give the entire leaf an almost cylindrical outline. The margins of the leaflets are either entire or have blunt teeth. Polystichum lemmonii grows in mountainous environments on ultramafic rock substrates, almost exclusively in serpentine soils or among serpentine rocks. While it only grows in very restricted geographic areas, it can become locally very abundant.
