Tuesday, June 28, 2011

6-27-11 Isoetes echinospora var. Braunii (in progress)

Hikers passing the outlet end of Lakes of the Clouds
looking from the middle of the lake, August 2010.

Last summer (2010) I explored the aquatic plants in several of the small, high lakes in the White Mountains. This included, east to west, Carter Lake (the larger of the two small lakes in Carter Notch), Lakes of the Clouds on Mt. Washington (the larger lake), Zealand Pond (near Zealand Notch and Zealand Falls Hut), Echo Lake on Mt. Lafayette, and Lonesome Lake on Cannon Mountain (near Lonesome Lake Hut).

During the summer of 1965 I assisted my colleague and friend, Larry Collins, in collecting data on the aquatic plants in five lakes including Partridge Lake in Littleton, NH, Profile Lake and Echo Lake in Franconia Notch, Eagle Lake on Mt. Lafayette and Lakes of the Clouds. Larry published the data under the title: "The Effect of Altitude on the Distribution of Aquatic Plants" as his master thesis at Dartmouth College. My cursory explorations in 2010 were designed to see if there have been significant changes in the distribution of these plants over the intervening 45 years. This summer I'll go back to Lakes of the Clouds and Eagle Lake and try to gather more definitive data about the plants in those two lakes than I had time to do last year.

Larry Collins and I identified this Quillwort in Lake of the Clouds as Isoetes echinospora Var. Braunii just as Slim Harris had in his series Plants of the Presidential Range published in Appalachia during the 1940s. This illustration and definition were taken from a reprint of Part V of the series; Ferns, Fern Allies and Conifers in the June 1944 issue of Appalachia:

In his Mountain Flowers of New England, published by the AMC in 1966, Slim changed his identification of the Lakes quillwort to Isoetes muricata with this small reference:

It's an interesting difference in the identification that I missed in 1965 and 1966, I guess I wasn't paying attention. The algae growing around the plants interests me as much as the species indentification. In all the lakes I explored last summer I observed a number of different kinds of plants that seemed to have a symbiotic relationship with algae. I'm not sure if this is the case with the Isoetes, or not.

Slim was a brilliant botanist so I'm curious if he keyed out a specimen or if it was an intelligent "guess". The incredibly extensive range of the muricata may make it a safer bet because it seems to everywhere. The range of the quillworts is another curios addendum to the boreal forest discussion: how did they get so dispersed? When did they disperse? They're a very old genus dating back to the evolution of the conifers so it's interesting to think about.

This summer I'll attempt to clear up the identification of this quillwort that's so plentiful on the bottom of Lake of the Clouds as well as compare Larry's 1965 data with current profiles for the plant communities in the other lakes. One reference point is the number of species found in 1965. At that time 20 species were found in Partridge Lake (the lowest of the lakes studied), 13 in Profile Lake, 9 in Echo Lake, 3 in Eagle Lake, and only 1, the quillwort, in Lake of the Clouds.

No comments: