What caused Chestnut Blight and what can we do to prevent it?

Answer 1

It was probably brought over from Asia in a load of trees that were brought to the USA in hopes of producing larger nuts. Asian trees are resistant to the blight, but the American chestnut is highly susceptible. Cryphonectria parasitica is a fungus that invades the tree through wounds of cracks in the tree's bark. Once the tree has been invaded, the fungus grows through the vascular cambium of the tree, eventually girdling the tree and killing it. A group of researchers from the Wisconsin Department of Natural Resources, West Virginia University, Michigan State University and Cornell University have set up a project to inoculate hypovirulent (less than virulent) strains of Cryphonectria parasitica into and around the cankers to try to contain the spread of the disease. The hypovirulent strains do not kill the trees and also prevent infection by virulent strains. There's some complicated genetics going on, and this is not as easy as it would first appear. Since the cankers can occur anywhere on the tree, professional tree climbers are called in to help inoculate the higher disease centers. It is an ambitious project and many volunteers gather every year to try to save these trees,

Answer 2

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