LE3 .A278 1996

1996

Vander Kloet, Sam

Acadia University

Bachelor of Science

Honours

Biology

Biology

Geum peckii Pursh and G. radiatum Michx. are two closely related perennial herbs of the section Acomastylis (Roscaceae: Geum). Both are endemic species, limited to the Appalachian Mountains, and for the former taxon, an outlying population on Brier Island, Nova Scotia. Historically G. peckii had been considered a variety of G. radiatum (sensu Gray, 1856, 1899), while Pursh described it as a species in 1814. Using the current treatment of the taxa, there are only two known localities for Geum peckii: Mount Washington, New Hampshire and Brier Island, Nova Scotia. Geum radiatum has been reported only from the Roan Mountains, North Carolina. There is wide current interest in plant population studies and their relevance to conservation efforts. In acquiring information on the life history of the species, assessments can be made as to how present management of a plant's habitat may influence the survival of its populations. The study of a plant population's reproductive biology indicates its sustainability, which could have further implications in habitat management, particularly those species with few populations. By using numerical taxonomy (clustering techniques), this study found no differences in floral nor vegetative characters to group 31 G. peckii and G. radiatum specimens into two species. Therefore the older name Geum radiatum Michx. is retained. The pollination study of Brier Island plants showed that the plants are pollinated by small flies. Nectar is produced sporadically. The flowers are protogynous and herkogamous, which serve as barriers to self-pollination, promoting cross-pollination. Experimental outcrossing produced a greater number of achenes (51-62; p=.04) than selfing (19-52; p=.04). That selfed plants produced some achenes indicated that the floral mechanisms provide only partial barriers to self-pollination.

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