Status Report On The Chestnut Castanea Dentata Marsh Borkh In Canada PDF Download

This report describes how the American chestnut (Castanea dentata) was ecologically extirpated due to an exotic pathogen, the chestnut blight (Cryphonectria parasitica), and describes current restoration efforts. The habitat, life history, special uses, and genetics of the American chestnut are detailed. The American chestnut was an important and versatile tree species until its demise from the chestnut blight. Backcross breeding techniques, the use of hypovirulent blight strains, and genetic engineering programs are currently being developed and tested to produce trees resistant to the blight fungus. The first putative blight-resistant trees have been planted and silvicultural techniques to improve competitive ability of chestnut are being tested. American chestnut is a fast-growing species with the ability to persist in shaded conditions and it responds favorably to forest management techniques that limit competition and increase available sunlight. Restoration will require advanced artificial regeneration techniques. The effects of damaging agents other than blight, including root rot caused by Phytophthora cinnamomi, Asiatic oak weevil (Cyrtepistomus castaneus), the gypsy moth (Lymantria dispar), and Asian ambrosia beetles (Coleoptera: Scolytidae) are not well understood but may represent real barriers to restoration.