A Closer Look at a Rare American Chestnut Tree in St. Anthony Park

July 2, 2018

American Elm in St. Anthony ParkThe American chestnut was one of the most important forest trees in the Eastern United States when Europeans first arrived and throughout the 19th Century. However, nearly all American chestnuts were wiped out by Cryphonectria parasitica, the fungus that causes chestnut blight, in the first half of the 20th Century. This fungus had been introduced into the U.S. on infected nursery stock in 1904. Surprisingly, a single chestnut tree seems to be growing in St. Anthony Park, not far from the St. Paul Campus, so Michelle Grabowski, Bob Blanchette and Nevin Young decided to take a closer look. They visited the unique tree in June this year, the time when the tree is flowering and quite beautiful, covered with long white catkins (flower spikes). It seems to be a tree 20-30 years old that has done comparatively well. Nevertheless, Blanchette quickly observed the symptoms of blight, especially a large canker high up in the tree along with nearby dying branches. With ready access to this fascinating living laboratory, plant pathology staff and students will want to re-visit the tree to learn more about its history and observe the disease progression in the coming months.