Climbing Fern

Ohio is a good state for Pteridologists - those who study ferns. We have nearly one hundred species, and if you are really into bedeviling yourself with maddening identifications (sometimes), there are many known hybrids.

The following fern isn't hard at all to recognize, although I'd bet few who read this have seen it, at least in Ohio. Climbing Fern, Lygodium palmatum, is one of three species in the Lygodiaceae (Climbing Fern Family). Ours is the only North American native; the other two species are Asian and sparingly introduced in Florida and nearby states.

I stopped by one of the only known Scioto County stations for it last Saturday to get my fix. Climbing Fern is known from only about eleven of our southernmost counties, and it normally is sparing in distribution and low in density. Vinton County, in the vicinity of McArthur, is the Ohio epicenter. There, I have seen it growing so thickly it looks like Japanese Honeysuckle from afar.

A typical Climbing Fern site - an open roadbank, in this case, cleared for a powerline right-of-way. The fern thickly festoons the vegetation, clambering up stems and forming a ground cover. It prefers acidic soils.

A closeup of the leaves, which are strongly dimorphic. The sterile pinnae (leaves) are palm or hand-shaped; the fertile pinnae are many forked and much more delicate.

A closer view of the sterile pinnae. This is quite a showy fern, with it's long-creeping wiry brown stems and lush, tropical-looking foliage.

In close on the fertile pinnae, which somewhat resemble the sterile leaves, just on a minute scale. The little whitish bumps on the segments of the leaves are the sori, or cases which hold the spores. As with all of our ferns, the tiny spores are windborn and can be transported great distances. I have heard that any sizeable air sample taken nearly anywhere in the world is likely to contain fern spores.

Climbing Fern is an exceptionally beautiful species, and forms luxuriant beds. It would be a natural for those interested in growing native species. I've not seen it in cultivation, but perhaps it is somewhere. The two Asian species are; escaping from cultivation is how they became established in Florida.