Invasive Scots Pine, Pinus sylvestris, Replacing Corema, Corema conradii, Heathland in the Annapolis Valley, Nova Scotia


  • Paul M. Catling Agriculture and AgriFood Canada, Environmental Health, Biodiversity, William Saunders Building, Central Experimental Farm, Ottawa, Ontario K1A 0C6
  • Susan Carbyn Agriculture and Agri-Food Canada, Environmental Health, Biodiversity, 32 Main Street, Kentville, Nova Scotia B4N 1J5



Scots Pine, Pinus sylvestris, Corema, Corema conradii, invasive, alien, heathland, barrens, Nova Scotia, Canada


Examination of air photos from 1930, 1970 and 2002 revealed stands of the European Scots Pine (Pinus sylvestris) invading remnants of natural Corema (Corema conradii) heathland in the Annapolis valley. To document the impact of the introduced pines, four natural habitats were compared with two adjacent habitats already invaded by the pines. All surveyed habitats had been dominated by Corema heath based on air photos taken in 1930. Twenty 1 m2 quadrats were used to record presence and cover of vascular plants at each site. The invasive alien pines reduce the native cover to 12%. Vascular plant biodiversity is reduced to less than 42% and the cover of the heathland dominant, Corema conradii, is reduced from over 100 % to less than 2%. with Deschampsia flexuosa becoming the dominant species. The modified ecosystem and loss of biodiversity has economic impacts through loss of pollinators of agricultural crops and loss of germplasm of native crop relatives.