Autumn Ferns 2025
Bracken Ferns
Autumn is still a great time to be out enjoying ferns. Besides the Dissected Grape Ferns which are the focus of our Fern Walk this Sunday (see calendar), Bracken Ferns (Pteridium aquilinum) are also worth looking at. I used to sort of ignore Bracken Ferns (except during fiddlehead season) because they are abundant, and common along roadsides and disturbed open areas. But they have become a lot more interesting to me, especially at this time of the year. Randy looked for years at any patch of Bracken Ferns he encountered, searching for fertile fronds with sori on the back. Until a few years ago, he had only found a couple, and not around here. Bracken Ferns are known for their deep horizontal underground rhizomes, which spread the plants, and are generally considered to be less dependent on sori to create new ferns.
But since then we have been occasionally finding fertile Bracken with sori around here. I don't know why that is, but it happened. We do have to hunt a bit. The Bracken Fern in this photo is on the Montague Pitch Pine Barrens. They are worth searching for this time of year, as you can see how attractive they are. The sori are located along the very edge of the leaflets.
Another interesting thing about Bracken Ferns is that some botanists are starting to use a slightly different scientific and common name for the ones found in Massachusetts and the Northeast. They are being called "Eagle Ferns" (Pteridium aquilinum variety latiusculum) on iNaturalist. Those names are not in the fern books we have, but sometimes there are comments about them on the web, for instance on Go Botany. It is a long process to get scientific names added or changed and I am sure there will be a lot of discussion and research done on this, but it is interesting. The word "aquilinum" is from the Latin "aquilus" and means "eagle". Depending on which source you read, authors claim that is due to the eagle-like appearance of the Bracken's early fiddlehead stage, or image in the cross-secton of the rhizome, or shape of the large wing-like fronds. I vote for the fiddlehead stage.
Bracken ferns are found around the world. They contain carcinogenic compounds that are toxic to animals and possibly people. Not to be eaten!
I have added information on the location of the Fern Walk this Sunday on the calendar listing. We think the rain will refresh the ferns and they will be glorious! We checked them out today and there are more new pretty little bright green ones in addition to the taller mature ones.
Posted: to PV Fern News on Wed, Sep 24, 2025
Updated: Wed, Sep 24, 2025
