Question

Since the expansion of international trade, Dutch elm disease and chestnut blight have nearly killed off the Dutch elm and chestnut trees in America. One might infer that these diseases were the result of _____.

Answer 1

Introduced species.....

Answer 2

Dutch Elm disease was mainly caused by elm bark beetles and it affected many countries in Europe and America and due to this chestnut trees were largely affected because leaves of the trees started appearing in yellow and at the time of Second World War it reached to Canada and most of the elm trees were killed by Dutch elm disease.