My favorite type of fern is the Autumn Fern, also known as the Japanese Shield Fern.

It is my favorite because it is lovely in fall and winter, when most of my other plants are dead or depressingly dormant.  It loves shade and moisture. It needs protection from wind to get this big without damage.

The fronds are bipinnate/twice-cut, which means there are two divisions of leaflets on the frond stem divisions. They are also triangular.

The sori are arranged in neat little rows along underside of the leaflets.

Its species name is Dryopteris erythrosora.   In Latin that means tree/fern/red/sorus.

A sorus is a packet of spores that looks like a rust spot this time of year.

Here are three sori under a microscope.  Each is a complicated system of catapults. The curled arms unfurl and sling the spores away from the parent plant.

Fresh sori are light colored or transparent. These still contain spores.

Spores are not seeds. They only have half the genetic material of the fern. These germinate into tiny “boy and girl” gametophytes,  which then get together and make the big “baby” sporophytes that we call ferns.

This ancient and strange life cycle is called “alternation of generations.”

I look at my ferns and feel a connection with prehistoric life.

Follow the FERN!