An Analysis of the Vascular Flora of Annapolis Heathlands, Nova Scotia

Résumé

A description and analysis of the vascular plant composition of heathlands in the Annapolis valley were undertaken to provide a basis for biodiversity preservation within a system of protected sites. Species presence and abundance were recorded at 23 remnant sites identified using topographic maps, air photos, and Nova Scotia Department of Natural Resources records. A total of 126 species was recorded, of which 94 were native and 31 introduced. The Annapolis heathland remnants are strongly dominated by Corema conradii with Comptonia peregrina, Vaccinium angustifolium and Pteridium aquilinum var. latiusculum. A number of species, including Solidago bicolor, Carex tonsa var. rugosperma, Dichanthelium depauperatum, Lechea intermedia, Melampyrum lineare, and Rubus hispidus, were characteristic of heathland remnants, although they usually contributed little to the total cover. The most frequent alien species were Hieracium pilosella and Festuca filiformis, but Pinus sylvestris, present at 7 of 18 sites, appeared to have the greatest impact in displacing native species. Species listed as at risk and sensitive in Nova Scotia, including Helianthemun canadense, Hudsonia ericoides and Viola sagittata var. ovata, occur in open disturbed sand in the Corema heathlands. Distinctive patterns of variation occur in several species and variation in crop relatives is noted with particular reference to the genera Rubus (blackberries), Amelanchier (Juneberries, Saskatoon) and Vaccinium (Blueberries). The available evidence suggests that the heathlands and sandy barrens in the Annapolis valley differ from those further west in Canada and from anthropogenic and coastal heathlands of Nova Scotia in their species composition including particularly the presence of Corema conradii, Hudsonia ericoides and Amelanchier lucida. The need to protect representative examples is supported.