Here's something you don't see every day...
|American chestnut (Castanea dentata) leaves.|
|Dad with an American Chestnut on Father's Day.|
Why am I speaking in the past tense? Because this tree species is now mostly gone due to the chestnut blight. Chestnut blight (Cryphonectria parasitica) is a fungal disease that evolved in Asia and was accidentally brought to the U. S. in the late 1800's, probably on furniture, lumber or nuts. Chinese Chestnut trees evolved with the disease, so they are resistant to it, but our trees were not resistant, and they succumbed to the disease as quickly as Native Americans died from European diseases introduced by the first European settlers of this land. The disease was discovered in 1904, and by 1950, almost all the American chestnut trees were dead, with only small shrubby root sprouts left surviving.
|Chestnut catkins (flowers). The narrow ones have only male flowers, the upper one has some pollinated female flowers, which will produce nuts.|
|Chestnut catkins with pollinated female flowers that have become burs, and male flowers above them.|
There are a few remaining adult American Chestnuts in North America. Many of the surviving ones are outside the former range for American Chestnut trees, so the blight hasn't spread easily to them. Also, there are different climactic conditions outside our chestnut's normal range, which cause the blight fungus to be weaker, or hypovirulent. Mom and Dad's chestnut trees are outside the normal range, so they may survive longer than other American Chestnuts. Of the original seeds they planted, about half remain. Their trees probably didn't die due to blight, but to non-ideal climactic conditions. Blight tends to affect teenage trees, and these trees are younger. It is likely that all my parents' trees will eventually die, unfortunately. Still, they may have a resistant tree, and their trees help maintain living tissue, help educate people about the trees, and help scientists learn more about what these trees need to survive. With so many people working to solve this ecological tragedy, it appears likely that American Chestnuts will eventually recover. I'm so proud of my parents for helping the American Chestnut!