FERNS IN NEWTON

Ferns are perennial, and almost all of them have emerged for the summer at this point. The Land Management Committee of the Newton Conservators has inventoried most of the open space within Newton, and posted their findings at newtonconservators.org/masterlist.htm We looked mostly at plants, but included birds, insects, and even mammals when we saw them. I was an advisor for pteridophyte plants (ferns, club-mosses, and horsetails.) We found 28 pteridophyte taxa: 21 fern species, 3 fern hybrids, 3 club-moss species, and 1 horsetail. For comparison, there are about 53 species of ferns native to Massachusetts.

Ferns and related groups are vascular plants, meaning that they have a circulatory system. They invented it, and it allows them and the flowering plants that evolved from them to get taller than the mosses, about four inches. In fact some of our ferns can grow to about seven feet. Ferns like mosses propagate by spores, tiny bits of genetic material that don't carry the food supply that seeds do. Ferns emerge as fiddleheads, uncurling spirals that keep the growth tip protected. (Only one species of fern, Ostrich fern, is legal for human consumption in North America. These are the "fiddleheads" in the produce department in the spring).

I described some of the ferns of Newton in the Newton Conservators Almanac. I discuss something of fern evolution and identification on my website: nefern.info/layouts/introduction_to_ferns.htm

The three best features to use in deciding which fern you are looking at are the degree of cutting, the growth form, and the stipe induement.

Most of our ferns are twice-cut; a few like Christmas fern and Polypody are once-cut; the laciest ferns are thrice-cut, or nearly so.

entire

once-cut

twice-cut

thrice-cut

The rhizome of a fern plant grows underground, and is equivalent to the stem and maybe branches of a spermatophyte plant. This rhizome can grow horizontally or vertically. Hayscented fern has a horizontal rhizome that branches frequently, and so the fronds grow up individually with no obvious spatial relationship among them. Ostrich and Wood ferns grow from a vertical rhizome; not only do the fronds come up in distinct clumps, but they face each other around a circle.

Some ferns have hairs on the lower stem, some have scales, some have neither. Cinnamon and Interrupted ferns have something like lint or wool.

I have photographs on my website of all of the native ferns of New England. You could send me a photograph of a fern you would like me to identify (don@nefern.info).

Some of our native ferns will do well in a home garden. I have at least 40 kinds in my small city yard in Allston, including about 2/3 of the Massachusetts natives. Most tolerate moderate shade, but would want to be watered if there is no rain for a week. Some require higher pH from e.g. cement or bricks or added lime. Mine vary in height from a few inches to five feet. I grow some exotic, e.g. Asian species, but I find better hardiness with native plants.

I have led several fern walks for the Newton Conservators, and may again sometime. We have found interesting diversity in Cold Spring Park, Nahanton Park and the Blue Heron Trail to its south, in Flowed Meadow, and in the Webster Conservation Area on both sides of Hammond Pond Parkway. Kennard, Edmands, Saw Mill Brook, and other relatively wild areas also have numerous ferns. I'm sure they would like you to visit.

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