Sori on a Polystichum Munitum Frond
Humboldt County, CA, USA
Ferns are well known and appreciated for their very divided fronds that usually have a distinct "ferny" look. While I love looking at a good fern, I always flip the frond over to check for sori (spore bearing structures) which are found on the bottom of mature fronds and are usually a rusty brown or orange color. They are usually very symmetrically arranged on the fronds and add a whole new level of beauty to them! These sori are also useful in identifying specific species of ferns. I urge you to flip over the fronds of any ferns you find to see if you can find the sori!