Chestnut Trees Fallen to Blight (IMAGE) University of California - Santa Barbara Caption This shows a range of chestnut trees that fell victim to chestnut blight. The disease, introduced to North America around 1900, is caused by the pathogenic fungus Cryphonectria parasitica. Credit University of California Santa Barbara Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.