Weissia brachycarpa (Nees & Homsch.) Jur. at Niagara Falls,

A Moss New to Ontario

P. M. Eckel
Res Botanica, a Missouri Botanical Garden Web site


Originally published in Canadian Field-Naturalist 111: 318-319. 1997.


Weissia brachycarpa (Nees & Homsch.) Jur. at Niagara Falls,

A Moss New to Ontario

P. M. Eckel

Clinton Herbarium, Buffalo Museum of Science, Buffalo, New York 14211

Eckel, P. M. 1997. Weissia brachycarpa (Nees & Homsch.) Jur. at Niagara Falls, a moss new to Ontario. Canadian Field-Naturalist 111(2): 318-319. A collection of the rare moss Weissia brachycarpa at Niagara Falls, is the first record for Ontario, the third Canadian province in which the species is known to occur. This plant is a noteworthy addition to the unusually rich biodiversity of the Niagara River Gorge.


Key Words: Moss, Weissia brachycarpa, Ontario, Niagara Falls.

During a study of the mosses of the Niagara River Gorge the following moss was discovered:


Weissia brachycarpa (Nees & Hornsch.) Jur. Canada: Ontario, Welland, Regional Municipality of Niagara, 4330'N, 7910'W. City of Niagara Falls: base of wooded embankment overlooking the Horseshoe (Canadian) Falls; in spray on calcareous clay in lawn; 28 May 1991, Eckel 9302250 (Buffalo Museum of Science).


According to Ireland et al. (1987) Weissia brachycarpa in Canada has been found in two provinces: British Columbia at one end of the country and Nova Scotia at the other. Stations reported for the United States by Crum and Anderson (1981) are located south to North Carolina and west to Texas, but otherwise the New World distribution is largely eastern North American. The Old World distribution includes temperate Europe east to the western states of the former Soviet Union. It is considered rare throughout its range (Crum and Anderson 1981).


Weissia brachycarpa has been recorded recently in New York State in nearby Niagara County (Eckel 1987) and just across the Niagara River from the Ontario station on Goat Island in the city of Niagara Falls, New York (Eckel and Eckel 1988). All collections were found at the margins of grassy areas by roadsides or in lawns, a habitat typical for the species. These are the only stations recorded in New York.


As with other species in the genus, now enlarged by the incorporation of Astomum (Stoneburner 1985), the plants cannot be identified if sterile. Capsules are necessary for their determination. The capsules of Weissia brachycarpa are distinctive in the smallness of the capsule opening, perhaps indicating a tendency of the species toward cleistocarpy, a feature of the subgenus Astomum. The capsules and leaves tend to be broader than a more common species, Weissia controversa Hedw., with which it could most easily be confused.


Other mosses found associated at the Ontario station were Amblystegium varium (Hedw.) Lindb., Barbula convoluta Hedw., B. unguiculata Hedw., Fissidens taxifolius Hedw., Phascum cuspidatum Hedw., Physcomitrium pyriforme (Hedw.) Hampe, Pleuridium subulatum (Hedw.) Rabenh., and Pottia truncata (Hedw.) Fuernr. All are typical of disturbed soil. Species found here but not recorded for Welland County (now part of the Regional Municipality of Niagara) according to Ireland and Cain (1975) are Barbula convoluta, B. unguiculata, Phascum cuspidatum and Pleuridium subulatum. The last species is known from only seven other stations in Ontario (Ireland and Ley 1992). Specimens of these mosses are deposited at BUF.


The Niagara River Gorge and its environs have supported a rich tradition of bryophyte interest beginning with such notables in the history of bryology as Thomas Drummond, collecting on the Canadian side in the early nineteenth century, continuing with John Macoun, Leo Lesquereux and T. P. James, among others, in the latter part of the nineteenth century. It was also then when Judge George W. Clinton, member of the Regents of the University of the State of New York, made systematic collections of interesting mosses on both sides of the Niagara River for distribution to various herbaria. Nearly all of these individuals included specimens collected at Niagara in exsiccatae distributed in the past century. That the moss flora still has populations of interest is supported by recent discoveries, such as Eucladium verticillatum (Brid.) Bruch & Schimp. in BSG in Ontario (Eckel 1990) and Didymodon australasiae var. umbrosus (C.Muell.) Zand. (Eckel 1986) and Bryum rubens Mitt. (Eckel and Shaw 1990) on the American side of the River.


The gorge of the Niagara River is the focus of the distributive power of converging transient human populations. It exists in the midst of several dense transportation networks, not to mention its function as a biological conduit for the Great Lakes watershed, the waters of which are constricted into a strait, bisecting and thereby creating the Niagara Peninsula. Such a concentration of vectors for diaspore movement are coupled with the gorge of the River: an unusual haven of relatively undisturbed complexes of microhabitats for the capture and retention of such diaspores. These conditions predate European migrations into the region, with the consequence that the gorge environment and the microhabitats along its rim contain nearly 75 percent of the biodiversity (of vascular plants) known for western New York and adjacent Ontario (Eckel, manuscript in preparation). The gorge appears to represent a biological sink for the chance seed or spore that happens into it. The extraordinary biodiversity of the Niagara River and gorge environment was noted earlier by David F. Day (1887).


Despite a return to the locality in every year subsequent to the original collection, I have been unable to rediscover the populations of Weissia brachycarpa. Whether this is due to their naturally ephemeral nature, to chemical lawn management, or to any of a number of other pressures characteristic of the natural and artificial environment of the area, is unknown.



Richard Zander determined the specimen collected at Niagara and the manuscript has benefited from his suggestions and comments. Permission to study the floras of the Niagara Gorge has been granted to the author by the Niagara Parks Commission, Ontario, and the New York State Department of Parks, Recreation and Historic Preservation. This study has been supported in part by a grant from the Niagara Frontier Chapter of the Adirondack Mountain Club.

Literature Cited

Crum, H. A. and L. E. Anderson. 1981. Mosses of Eastern North America. Columbia University Press, New York.

Day, D. F. 1887. Catalogue of the Niagara Flora. Annual Report of the Commission for the State Reservation at Niagara for the Year 1887: 67-133. Also reprinted as pamphlet, Troy, New York. 1888.

Eckel, P. M. 1987. Mosses new and rare for New York State. Rhodora 89:375-379.

Eckel, P. M. 1986. Didymodon australasiae var. umbrosus (Musci: Polliaceae) new lo eastern North America. Bryologist 89:70-72.

Eckel, P. M. 1990. Eucladium verticillatum (Musci) second Ontario station. Evansia 7: 15.

Eckel, P. M., and M. P. Eckel. 1988. Weissia hedwigii on Goat Island, second locality in New York State. 1988. Clintonia 3(3): 8-9

Eckel, P. M., and J. Shaw. 1990. Bryum rubens from Niagara Falls, new to New York State. Bryologist 94(1): 80-81.

Ireland, R. R., G. R. Brassard, W. B. Schofield, and D. H. Vitt. 1987. Checklist of the mosses of Canada II. Lindbergia 13:1-62.

Ireland, R. R., and R. F. Cain. 1975. Checklist of the Mosses of Ontario. National Museums of Canada Publications in Botany 5, Ottawa.

Ireland, R. R., and L. M. Ley. 1992. Atlas of Ontario Mosses. Canadian Museum of Nature, Syllogeus (Canadian Museum of Nature, Ottawa, Ontario) 70: 1-138.

Stoneburner, A. 1985 [1986]. Variation and taxonomy of Weissia in the southwestern United States. II. Taxonomic treatment. Bryologist 88:293-314.


Received 19 July 1996

Accepted 20 October 1996