Castanea dentata (Marsh.) Borkh.
Castanea americana (Michx.) Raf.
American chestnut trees are, not surprisingly, a North American native species, once so abundant they are estimated to have comprised 25-30% of all hardwoods in their natural range in eastern North America. Now they have been decimated by a fungal pathogen called chestnut blight fungus (Cryphonectria parasitica). Remarkably, although this fungus killed most chestnuts back to the ground in the 1930s and 40s, many of those stumps still produce viable sprouts. Unfortunately, the young trees only rarely last long enough to produce nuts. Many efforts are underway to produce more blight-resistant hybrids.
Identification: Trees reach up to 98' (30 m) in height and 9½' (3 m) in diameter. Well they did, that is, before the chestnut blight started killing mature trees as well as saplings by the time they reached 20' (6.1 m) or so in height. Now this is pretty much their upper height limit over most of their original range. Ironically, these majestic trees that were once called the redwoods of the east.
Leaves are oblong to lanceolate, alternate, 6-8" (14-20 cm) × 2½-4" (7-10 cm), with sharp dentate “saw teeth” and pinnate veins. Male flowers are small, pale green, packed tightly along catkins that are 6-8" (15-20 cm) long. Fruits are round, sharply spiny husks 2-2½" (5-6.3 cm) across, which dry and crack open to reveal 2-3 polished burgundy brown nuts, roughly round but squeezed into funny shapes by pressure against neighboring nuts. Each nut is ½-1" (1.3-2.5 cm) around, with a round, tan-colored patch about ⅜" (1 cm) in diameter.
Edibility: Chestnuts from many species are edible; these are smaller than some but also sweeter. Nutmeats are dried and powdered, then added to flour to make cakes and breads. Roasted chestnuts may be shelled and eaten, or used as coffee or chocolate substitutes. Because the American species is semi-extinct, European chestnuts are the primary source of these edible nuts now.
Castanea dentata on Discover Life
Castanea dentata at the Virginia Tech Department of Forest Resources and Environmental Conservation
Castanea dentata on www.npr.org
Castanea dentata on Plants for a Future, a resource and information centre for edible and otherwise useful plants
Castanea dentata on Wikipedia
Castanea dentata on www.carolinanature.com
Castanea dentata at the Lady Bird Johnson Wildflower Center
Castanea dentata on eFloras
Castanea dentata description by Thomas H. Kent, last updated 12 Oct 2018.
Range: Zones 5-8: