Asplenium rhizophyllum

I know this is a wildflower blog, but occasionally a non-flowering plant makes its way into my heart too. Here’s one that I’ve photographed now and then through the years. It is called Walking Fern.

I feel like a little kid when I come across Walking Fern on my hikes. I felt this way about strawberry plants too when I first learned that they could reproduce by “walking”.  Of course what I’m talking about is the ability of these plants to produce “runners” that bear new “baby plants”. The babies are as cute as can be, and being able to trace the baby’s parentage by following the thread back to its origin is simply endearing! Each parent-child team tells a tender story, so I usually stop for a while when I see this fern species–just to soak in all the magic 🙂

But I digress…

Walking Fern is one of the small, but distinctive ferns you can expect to find growing on moist and well-shaded limestone rocks in the Appalachian Mountains. The long, narrow, triangular fronds are evergreen, so you can usually spot this species year-round. The tip of the frond can grow very long, eventually forming a “runner”.  If the tip of the runner touches a suitable spot nearby, a new plant can take root.

As you can see in the gallery below, young plants tend to hug the surface of the rock but older plants will gain some height over time and take on an arching form. When dozens of these plants grow in the same place, the resulting “vegetative colony” can look like a thick, stringy mat of greenery.  I don’t see these colonies very often, but we found a large clump like this on a recent walk to Mill Creek Nature Park in Narrows, VA, hence today’s blog post!

In addition to cloning themselves by “walking”, these ferns can reproduce via microscopic spores. If you flip over the fronds, you can sometimes see the brown spore-producing structures, called sori, lining the underside (see the gallery). By using a hand lens or dissecting microscope, trained botanists can examine the tiny sori in order to key a fern out to species.

Walking Fern cascading over a limestone rock next to Mill Creek

Walking Fern growing alongside moss on a limestone outcropping at Falls Ridge Nature Preserve

Walking ferns and moss like the same habitats!

Individual frond with thread-like tip

Underside of frond showing the sori

Walking fern on limestone

A “vegetative colony” of walking fern

Note the elongated tips of the fronds

The brown sori of walking fern