A few hundred years ago North America's forests were dominated by the American chestnut. It stood as the dominant hardwood tree in most of the continents forests, much like oaks do today. It also occupied a similar place in the food chain at the time to what oaks occupy now. Chestnuts served as the primary food source for wildlife in the fall, the preferred food for deer, turkeys, squirrels, and many others. They provided the necessary carbohydrate and fat source animals needed to supply energy for the winter. Humans also relied on the nuts heavily for food as they are palatable and nutritious and do not contain the tannins present in acorns. Chestnuts were an extremely important part of life just a few hundred years ago, and they had been an extremely important part of the ecology of Eastern North America for thousands of years.
Today however, we rarely see a chestnut tree. Their place in nature has been largely taken by the oaks we see in today's Eastern hardwood forests. Acorns have become the fall food source of most wildlife, but this isn't by choice. Acorns are simply the next best thing deer and turkeys have available to them today because Americas chestnut trees were killed off by by a plague brought by humans from Asia.
Known as Chestnut Blight, this fungus arrived in the US in the early 1900's and quickly killed Americas vast forests of chestnut trees in less than 40 years. This has been called one of the worst ecological disasters in history as the demise of the American chestnut struck a huge blow to the ecology of North America. This heavily relied upon food source was gone almost overnight. As forests has recovered, other tree species such as oaks have come to fill the role chestnuts once served in the environment, but these species are simply stand ins for America's original hard mast tree.
In the mid 1900's, a few surviving American Chestnut trees were found growing in the wild after all others had been killed off by the blight. These surviving wild American chestnuts were taken and hybridized with Chinese chestnuts, which are naturally immune to the blight. After years of selective breeding and further hybridization the product of this was what is now known as the Hybrid Chestnut. These chestnuts are resistant to the blight that had killed the American chestnut and also have superior nut production to them as well. Hybrid chestnuts bear nuts very quickly, in just 2-5 years, and they bear larger nuts and more prolific crops than the original American chestnut. This variety has come to be the preferred planting for wildlife managers everywhere as it has all the characteristics to make it useful as a food source for wildlife.
With the rise of the hybrid chestnut, the chestnut can once again return to America's forests to fill the role it once did as the preferred hard mast tree for deer and turkeys. Land managers everywhere are seeing the benefits of planting these hybrid chestnuts for wildlife. These plantings consistently outperform oaks and fruit trees in terms of survival, quick production, food value to wildlife, and attractiveness as they often become a destination food source for wildlife.
Recently, work has been done to bring back the American chestnut in it's original form with no genetics from other varieties. Researchers are working to genetically modify American chestnuts to give them blight resistance on their own without the need to hybridize. The work has been largely successful and many hope these pure American chestnuts will be available in the coming years. For now though, they remain tied up in governmental regulation and development.
Despite the decades long absence of chestnuts from most habitat, wildlife still greatly prefer their natural food source of chestnuts when given the choice. (To read more about wildlife's preference for chestnuts see our post "Chestnuts: The Preferred Food Source for Deer") Deer are simply hardwired to eat chestnuts. Thousands of years of preference doesn't die as easily as the native chestnuts of days gone by. Whether its genetic or otherwise no-one can say for sure, but one thing that's clear is that deer still have a taste for chestnuts. In areas where no chestnuts have grown for over 100yrs deer will still feed on them immediately with no learning curve like is often seen when introducing new food sources like beets and other brassicas. If you want to see what we mean, try getting your hands on some harvested chestnut nuts and a trail camera. We've done this at multiple locations and got footage of dozens of deer feeding on the pile for hours until they were all cleaned up.
If you want to return your habitat to the way it once was, and supply wildlife with a food source that will become a destination for deer and turkeys, consider planting hybrid chestnuts on your land this year.