I posted Three ferns for ID three years ago, and two of them were ferns I've been wondering about for a while in the West End. I finally came up with some names, two of which were in that posting. I have just posted the Matteuccia struthiopteris in another thread. Here is Pteridium aquilinum, bracken or brake fern. Please correct me if I have this ID wrong. I have heard the term "bracken" forever, but had no idea what it looked like. There is a child who I hope is mostly obscured, at the right of the first photo, giving an idea of the size. What interested me about this is the level of divisions on the leaves, on some twice pinnate, others three-times pinnate, or different on different parts of the leaflets. Are there sori starting to develop on the pinnulet margins on the last photo in this set? I guess I should have called the whole thing here "frond" rather than leaf. It's way too much trouble to fix that now.
Here is some bracken fern from long time ago during a hiking trip in Scotland, during a heatwave. I love the way it covers almost entire hillsides.
Hi Wendy, yes, everywhere I have seen this one has been an exposed low hill, somewhat dry conditions... very unusual for a fern, but it thrives in such areas. The one in your pictures is a particularly large example, the ones I have seen in the wild (different places and countries) are typically half that size.
Yep - Bracken is definitely not a species to plant deliberately, very invasive! It forms extensive clonal colonies from rhizomes deep underground; a single colony can cover many hectares. I'd not have said Wendy's plants were unusually large, it often grows to 2-3 metres tall where conditions are good for it. The smaller ones Nik mentions were likely on infertile soil and/or in exposed sites.
@Margot just posted a link to this Bracken fern video in another thread: Bracken Ferns - How to Identify Them! || Nerdy About Nature Flora Guide - YouTube