Massachusetts fern is not a rare fern, yet it was not discovered until 1894. To a casual glance, it looks like a marsh fern.
- Synonyms: Thelypteris simulata
- Family: marsh fern (Thelypteridaceae)
- Habitat: moist, acid woods and swamps, especially cedar swamps
- Height: 18 to 30 inches
- Location of spores: underside of fronds
- Petiole (leaf stalk): green to yellow-brown, with a few scales at the base
- Growth pattern: random
- Persistence: deciduous
- Origin: native
Underside of a fertile leaflet, showing the kidney-shaped sori (spore-bearing dots). Note that the leaf edges are not rolled around the sori; this is the easiest way to distinguish Massachusetts fern from the similar-looking marsh fern. Also, Massachusetts fern has veins that are unforked, while marsh fern has mostly forked veins.