Last Thursday (September 28) I was on a mushroom walk (I'll try to post on it, too) near Lion's Head on the Bruce Peninsula. At the beginning of the walk, we came across a large northern holly fern (Polystichum lonchitis). We repeatedly found other though less spectacular specimens later on the walk. This species occurs in a number of locations on the Niagara escarpment in Grey county and on the Bruce.Boughton Cobb in A Field Guide to the Ferns and Their Related Families of Northwestern and Central North America has the following "helpful" note on p. 55:
"P. Lonchitis, the Northern Holly Fern, found extremely locally in our most northerly and middle-western area, is not illustrated. This species is found locally only on cliffs of our Canadian border."
Right, we don't exist and, therefore, there is no point in illustrating this species. He could have at least put United States instead of North America in the title to warn us. Fortunately, I own a copy of the Ferns of Grey and Bruce Counties, Ontario by the Bruce-Grey Plant Committee (Owen Sound Field Naturalists), a splendid little guide to the ferns in my area. It gives this beautiful plant its due.
This is a large fern with some of the fronds of the specimen pictured measuring almost 70 cm. It forms a bright green patch in the forest as it assumes its bright fall colours and essentially turns towards its wintery shades of brown. Like the closely related Christmas fern and polypody, it is evergreen.
I encountered another interesting fern a month earlier when I was camping and canoeing in Algonquin Park. This one is a leathery grape fern (Botrychium multifidium) that was growing on the abandoned Mew Lake airfield, a large open area in the Highway 60 corridor. Among the grass, lichens, shrubs and slowly invading trees, it formed a small patch of a few individuals. It's an odd fern that is closely related to the rattlesnake fern I wrote about a while back. In a way I was surprised to find it in such a disturbed habitat as the old airfield. However, Cobb writes that it likes drier, more acid and sandy locations, so the airfield is a good match (p. 190). By contrast, the rattlesnake fern likes "rich, moist or dry woodlands" (p. 192).
While canoeing on Rock Lake on the saame trip, we stopped near some cliffs for a lunch break. On one of the boulders I saw this colony of common polypody or rock cap ferns (Polypodium virginianum). The rhizomes of this species form a thick tangle across the rock surface where the plant must be able to withstand dry conditions. By counting the "footprints" on the rhizome, the tiny scars left behind where dead fronds have fallen off, it is possible to estimate a colony's age and it has been found that some have sustained themselves for several decades. Apart from the habitat, it is easily told by the shape of the fronds and their relative small size from its relatives, the northern holly and Christmas fern.
Another find on this trip was this spinulose woodfern (Dryopteris spinulosa). This fern is nothing unusual in a sense, it is a common woodland fern, but with its classical upright fern shape it still is a sight that gladdens my heart every time I see it -- a kind of reassurance that some things in the world are still right. This specimen was found in the upper parts of the Mizzy Lake Trail near Wolfhowl Lake.A week later, my wife found another interesting fern on a canoe trip near Temagami. The picture is a bit blurry but I think it is clearly recognizable as an alpine woodsia (Woodsia alpina). This is a high altitude and northerly species that doesn't even occur in Bruce and Grey counties and it was my local guide's turn to draw a blank. Well, at least this one made it into Cobb because it occurs in several New England states. I guess it's worthwhile having more than one guide. It's typically a small plant, as a comparison with the pine needles quickly shows, so it's a combination of good luck and observation that it was noticed.
That's it for this posting. I'll try to write in more detail about the Algonquin Park trip some other time.
