Native to North America, boxelder (Acer negundo) trees are fast-growing, drought-resistant maple trees that produce minimal maple. These trees are also called box elder trees, ash-leaved maple and Manitoba maple. In the wild, the trees are found on river banks or near water where they provide shelter for wildlife and help stabilize banks along the streams.
Homeowners sometimes plant them as an easy-to-grow decorative addition to their gardens, and they serve as wonderful climbing trees for young children. In urban areas, however, they're often found in ditches and viewed as a weed.
These hardy trees can grow in zones two through nine, surviving most mild, cool or cold regions of the country. Plant your boxelder near a stream or river, if possible. Boxelder maples will survive in most soils, sand or clay, regardless if it's wet or dry, but they're sensitive to salt spray. They require six hours of direct light daily and are extremely sensitive to wind and ice damage. Boxelder trees are considered an aggressive tree as they easily germinate.
Boxelder Tree Identification
Boxelder is unusual for a maple tree, featuring compound leaves that are ash-colored, thick twigs that transform from powder blue to purple-green as the season progresses and roundish buds. This maple tree has a brown bark trunk and its lumber is distinctively softer, weaker and lighter than the majority of maples. Boxelder maples are prone to extreme sucker growth, and when wet, they have an unusual and foul smell.
There are both male and female boxelder maples, identified because only one type of flower — the male or the female — is found on the tree. Blossoms on the female trees become bright green when pollinated. Only the female trees produce samara fruits. These fruits, often called "helicopters," feature winged seeds that are approximately 1.5 inches long and V-shaped. During the winter, female trees will often maintain some of their helicopters.
Boxelder Tree Uses
Because their wood is soft and weak, these trees have no large commercial value. However, the wood is easy to work with by hand and machine. People often turn to boxelder maple wood when making turned objects and small ornamental objects as well as wood pulp and charcoal. They're also easy to glue and finish nicely, so you may also find boxes and crates made from boxelder maple.
Boxelder Tree Pests and Dangers
Boxelder female trees attract small, approximately ½-inch-long boxelder bugs that are either red or black and feature thin lines on their backs. These bugs suck the juices from boxelder maple trees but don't really harm the tree. While they aren't a nuisance in the garden, they do prefer warmth, so odds are you'll find them joining you in your home once winter arrives. Although they're mostly considered an annoyance, they can puncture human skin and cause minor irritation. Their fecal matter can stain your curtains or other items where they've chosen to reside.
Indoors, you can eliminate boxelder bugs with your vacuum cleaner or you can spray an insecticide around the baseboards and window seals. To prevent them from entering your home, spray your home's exterior walls in late spring and the fall with a residual insecticide. You should also seal all exterior cracks, or as many as possible, during the summer months to prevent entry.
Like other maples, boxelder maples may cause skin irritation, a runny nose and asthma-like symptoms. However, they're fatal to horses who eat a significant amount of their seeds. Boxelder maple seeds contain a toxin that has been associated with seasonal pasture myopathy, which will block a horse's fat metabolism and also cause the breaking down of the animal's respiratory and postural muscle cells. Although horses rarely eat these seeds, it's wise to remove these trees from areas where horses may graze.