Extension Educator, Horticulture
"Chestnuts roasting on an open fire. Jack Frost nipping at my nose". We know all about Jack Frost. He recently nipped at my nose; then promptly chewed it off. The smell of chestnuts roasting on an open fire -- a rare experience. One hundred and fifty years ago Americans could have roasted 'em, toasted 'em, ground 'em, fed 'em to the hogs and fed 'em to the kids. Chestnuts covered the forest floor of the Appalachians from Maine to Florida.
American chestnut trees (Castanea dentata) were once the king of the forest reigning over 200 million acres. In the eastern U.S. one fourth of the hardwood trees were American chestnut with an estimated 4 billion in their native range. Chestnuts dominated the landscape, stretching 150 feet tall and 100 feet wide with a trunk diameter of up to ten feet. What a king!
But the king had an Achilles heel. First identified in 1904 at the Bronx Zoo the fungus, Cryphonectria parasitica, now known as chestnut blight quickly engulfed landscape and forest. The fungus was likely an unnoticed hitchhiker on imported Japanese chestnut trees. In less than 50 years chestnut blight virtually eliminated an estimated 3.5 billion trees.
Asian chestnut species co-evolved with the fungus developing some resistance or tolerance to the fungus. However the American chestnut was completely vulnerable to the exotic invader. The fungus infects a tree through wounds. The damage from the fungus eventually girdles the tree; however it does not affect the roots. Trees begin a cycle of doom resprouting only to have stems killed.
The loss of the American chestnut was devastating to the regional economy and gastronomy. The king had provided for his subjects. A mountain woman once remarked, "A grove of chestnuts is a better provider than a man – easier to have around too." Bears, birds and brethren relied on the nut crop for food. Hogs were fattened under the gaze of the king. People bowed at the king's feet as they gathered the bountiful nuts. Chestnuts were traded at local stores for staples of flour and sugar. As a cash crop, nuts were shipped to cities where street vendors sold hot roasted nuts.
The king sacrificed himself as well. From cradle to coffin chestnut lumber was a valuable commodity. The wood was tough as oak but lighter weight and as rot resistant as redwood. Logger's lore recounts stories of loading entire railroad cars with boards cut from just one tree. Chestnut was used for practically everything from fence posts, railroad ties, barn beams and home construction to fine furniture and musical instruments. Chestnut bark was a source of tannins for the leather industry.
In Illinois where oak is king American chestnut was native to only a county or two in southern Illinois. Found in other parts of Illinois they were likely planted by early settlers. Chinese chestnut trees are found throughout Illinois, but they never reach the stature of their kingly cousin. If you are a gatherer, be sure not to confuse the poisonous horsechestnuts and buckeyes.
With such a valuable provider researchers have spent decades looking for blight resistance. However breeding for resistance is a laborious, time-consuming endeavor. The American Chestnut Foundation along with its partners the U.S. Forest Service and universities have promising results. By using the blight resistance of Asian chestnuts and a breeding method known as backcrossing, six generations later the end result is a blight resistant American chestnut retaining 94% American chestnut genetics.
Over the last couple years a few thousand of these promising blight resistant trees have been planted in North Carolina, Tennessee and Virginia. Although it will take years to know if the super chestnuts will thrive in a chestnut blight world, future generations may once again know the smell of chestnuts roasting on an open fire.