American chestnut sprout survival with biological control of the chestnut-blight fungus population
Forest Ecology and Management 152(1/3): 225-233
The American chestnut trees (Castanea crenata) in Connecticut were reduced to understorey shrubs by an imported fungus that causes lethal cankers. Chestnut blight (Cryphonectria parasitica) disease was first reported in the USA in 1904, and in Connecticut in 1907. Hypovirulence is a virus disease of the fungus that reduces its virulence enough to allow the defence systems of the trees to restrict the fungus to the outer bark.