Athyrium filix-femina subsp. cyclosorum: Subarctic Lady Fern

Athyrium filix-femina subsp. cyclosorum, the Subarctic Lady Fern or Western Lady Fern, is a large, robust, deciduous fern native to western North America. It forms a vase-shaped clump of bipinnate to tripinnate fronds up to 4-5 feet tall. The sori are round (cyclosorum) and the indusium is often horseshoe-shaped. It is a vigorous, variable subspecies of the common lady fern.

Plant Profile

This lady fern thrives in moist, humus-rich soil in partial to full shade. It is a dominant understory plant in northwestern forests. It is excellent for large woodland gardens, stream banks, and wet meadows in cool climates. The round sori distinguish it from the typical subspecies. A bold, native fern for the western shade garden.