Swamp Fern (Blechnum serrulatum), also called Blechnum Fern, toothed midsorus fern, and saw fern, is native to Florida, the Caribbean, and Central and South America. It grows best in moist, shady locations including swamps, marshes, wet prairies and hammocks. Under optimal conditions, it reaches a height of 36 to 48 inches.

As shown in the first two photographs, fronds are pinnate with a single, apical leaflet. This extra leaflet on the end of a frond distinguishes it from Boston fern (Nephrolepis exaltata).

Shown below, leaflets are crinkled with serrated edges. By running your fingers backwards along the swamp fern's frond edges, you can feel the serrations. The species name "serrulatum" means "small-toothed."

New frond growth is coppery pink, and as a frond ages, it becomes dark green.

Swamp fern propagates with dividing rhizomes and spores.

You will see many swamp ferns growing along the Conservancy of Southwest Florida Nature Center's Hammock trail.