American Hornbeam (Carpinus caroliniana) is a small, slow-growing tree of moist woodlands. Another common name for this species is musclewood, appropriate given that the trunks (and large branches) resemble taut muscles and that the wood is incredibly dense and durable. Think of Carpinus caroliniana as a body-builder of the understory.
American Hornbeam is a member of the Birch family (Betulaceae), and like most members of that family has leaf margins that are double-toothed (that is, with a series of smaller teeth occurring between larger teeth). Mature trees flower in the spring and by fall bear ripe clusters of winged nutlets.
At times, I've confused the common name of this tree with that of Hop-hornbeam (Ostrya virginiana), a related small tree with similarly dense wood, but vastly different bark that consists of thin, exfoliating strips (see labeled photo below). Hopefully, you'll have an easier time keeping them straight.
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