Return to Native Trees of the Southern Rocky Mountains

The Boxelder is a kind of maple, or very close to being a maple, though its leaves are unlike common maple leaves. The Boxelder is the only large maple of the plains and eastern low foothills of the southern Rockies. Boxelder usually grows along streams. It also grows in mountain canyons and valleys, and in lower parts of the Rio Grande and Colorado River basins. Its elevation range is 4500 to 7500 feet.

The Boxelder is short-lived but grows rapidly, especially at first, and is resistant to drought, heat, and cold. This tree rarely reaches 75 feet in height or 100 years in age. It often divides into several stems a few feet above the ground. The wood is weak and has little use as timber. Since Boxelder is resistant to drought and cold, it is planted as a shade tree in rural communities, and was widely used for shelter belts. Towns in South Dakota and Utah are named for this useful tree of the sun-baked west. The extreme drought of the 1930s on the Great Plains killed nearly all the Boxelder there.

This maple of the plains provides sap suitable for making maple syrup. The syrup made from Boxelder is said to be not as sweet as the sugar from the true sugar maple, but it was nevertheless a welcome resource on the plains of Colorado to natives and early settlers alike. All tribes of the Missouri river basin and northeastern Colorado used Boxelder syrup of old, and as recently as early this century too. For those who wish to try, the trees are tapped during the early sap run near the end of winter, probably March in the southern part of its range here.

Magpies prefer Boxelder for their nests. Evening grosbeaks and mice eat the seeds, as do squirrels and chipmunks, who also store the seeds in ground caches. Unclaimed seeds sometimes sprout into new trees. Mule deer occasionally browse leaves and twigs.

The new scientific name of the Boxelder in Colorado is Negundo aceroides var. interius . Negundo is a Malay term for a tree with similar leaves, and aceroides means "maple like" from acer, maple. It was formerly called Acer negundo. The Boxelder grows naturally in northern Europe and was first described there by Linneaus in 1753. A new so-called common name is Ashleaf maple which is not likely to replace the name Box Elder any time soon.

Leaves: Compound, 3 to 5 leaflets (rarely 7), 4 to 10 inches long; leaflets 2 to 4 inches long, 1 1/2 to 2 1/2 inches wide with large teeth or sometimes lobed; light green.Leafstalks persist in winter on stems, after the leaf blades have fallen.

Fruit: 2-winged samara 1 to 2 inches long, diverging about 90 degrees or somewhat less.

Stems: Twigs and buds are opposite on the stems. Boxelder is one of the few Colorado native broad-leaf trees with this characteristic. Branchlets covered with short hairs. Variety violaceum has smooth twigs. New twigs smooth and greenish with a gray cast.

Bark: pale gray-brown and ridged on young trees with vertical ridges; dark, and rough or knobby, on old trees.