Someone asked me about ferns and, aside from their unusual (blush) life cycle, I don’t know a lot about them, so I did what I usually do. I looked them up. There are 10,000 kinds of ferns. That is enough to make me cringe. I don’t want to be an expert. I just want a little information please. Well, my hubby, Metric Man, studied botany, so he got down some of his old books.
They turned out to be very old books because, when I checked them with things on the net, there was a huge difference in
information. Out came the newest book which is just on ferns in Costa Rica, but it was still dated 1989. Very sad, so back to the net.
Well, there seems to be agreement on four classes of ferns (some botanists say five [jeesh guys, make up your minds]) alive today and another four extinct classes. As much as I love hunting fossils, lets just stick to the live ones. The largest of the classes is the Polypodiopsida or Leptosporangiate ferns. Lets just call them the true ferns since that is how the American Fern Society (an international group) refers to them.
True ferns are the most common and the society states that there are about 12,000 different species around today. Luckily, the society has a lot of pictures to use for comparison with ferns you see in the wild, and they all come with names. What a relief. Still, with 12,000 species, finding out exactly what you have growing in sun or shade will be tricky. [It would be nice to stick with the class, Equisetopsida (horsetails), it, blessedly, has only 15 species, but you don’t see them much…]
So what, exactly, makes a fern a fern? Ferns have roots and stems (called rhizomes) like normal plants, but they have fronds instead of leaves, even though leaves and fronds have the same purpose. Fronds can be as small as 1/16 of an inch in length in the mosquito fern to 12 feet in length. Ferns don’t make flowers or seeds. Instead, they reproduce by spores, a tricky process. Spores develop on the bottom of the frond in all species of ferns except one (there had to be an exception).
The whisk fern (Psilotum) has its spores on the tips of fronds and the fronds are unusual as well. The fern society calls it: “probably the most primitive vascular plant still in existence” and suggest it is related to the first land plants.
Well, I hope that aroused your interest in this ancient group of plants. As for me, I am going to be looking for whisk ferns from now on.