lady fern

Lady fern is a relatively large, decorative, feathery fern. It is native to Europe, Asia, and North America. It occurs throughout the United States and southern Canada where it is most common east of the Great Plains and west of the Rocky Mountains. It is mostly absent from the great Plains. It occurs throughout Minnesota but is uncommon in the southwest region and in the westernmost counties.

Lady fern is found in a variety of habitats, including bottomland forests, moist woods, meadows, thickets, swamps, and streambanks. It grows under dappled sunlight to moderate shade, in loose, moist to moderately moist, loamy, slightly acidic soil.

Lady fern is often cultivated for its attractive foliage as a garden ornamental. It is relatively easy to grow and relatively pest-free and disease-free. It also provides food and shelter for a variety of animals. It has been used to treat a variety of ailments, including arthritis, gout, and kidney stones.

Lady fern is a relatively large, delicate, perennial fern. Several fronds rise from a short-creeping rhizome and fibrous roots, forming a compact, more or less circular cluster.

The fronds are deciduous, up to 120 cm long, light green, and lacy in appearance. They are divided into 30 to 40 leaflets (pinnae), and the pinnae are divided into smaller pinnules.

The stem (stipe) has numerous, scattered, brown to dark brown, linear to egg lance-shaped, chaffy scales.

Fertile and infertile fronds are similar in appearance. The spore-bearing structures (sori) on the underside of fertile fronds are kidney-shaped and covered by a protective veil (indusium). The indusium is attached to one side of the sorus.

Sources

2, 3, 4, 5, 7, 28, 29, 30.

There is considerable disagreement on the number and classification of the varieties of Athyrium filix-femina. Four varieties were traditionally recognized. The names of the varieties are one source of disagreement. Various authors have elevated one or more of the varieties to full species status. How many and which ones is another source of disagreement. Of the varieties, only northern lady fern (Athyrium filix-femina var. angustum) occurs outside of cultivation in Minnesota. When treated as a species, it is Athyrium angustum.

Update
Since 2019, the separation of eastern North American Athyrium filix-femina var. angustum as a distinct species has grown considerably. However, many highly respected sources, including Flora of North America, GRIN, and USDA Plants, have not accepted the change.