An Introduction to the Boxelder Tree

Boxelder trees, also known as ash-leaved maples, are one of the most common and adaptable urban trees in North America—though they also may be the "messiest" from a visual perspective. The boxelder is very commonly seen in treeless plains and flanking the streets west of the Mississippi River.

It seems that the tree takes on positive characteristics not seen in the eastern half of North America in its western habitat. California interior boxelders take on yellow and red colors in autumn that rival eastern maple. Its drought tolerance makes the tree great for dry country landscapes and very easy on limited water resources. The best thing about it is that it's comfortable on poor sites where more desirable trees cannot maintain adequate health for a long life.

Learn more about the ubiquitous boxelder, including how to identify it, how to grow and maintain it, and problems that could come up.

About the Boxelder

The boxelder (Acer negundo) also goes by ashleaf maple, Manitoba maple, and poison ivy tree. It's a member of the plant family Aceraceae. Although considered a "maple outcast" by many, it is indeed in the maple family and the only native maple with more than one blade or leaflet on a single leaf stalk.

Boxelder is native to North America and grows in USDA Plant Hardiness Zones 3 through 8. It's very common throughout the western U.S.​

The tree is crafted into bonsai specimens and used as a screen or windbreak and for land reclamation. Boxelders often have multiple furrowed trunks or very squat single trunks. It grows rapidly and large (25 to 50 feet). One of the tallest ever measured had a recorded height of 110 feet. The tree's crown spread is 25 to 45 feet, and the crown is typically broad and ragged or disheveled. For this reason—and its proneness to breakage—it's not recommended to plant one in your yard.

Flowers are without petals, dioecious, and yellowish-green, and the female tassels are very conspicuous. The very maple-looking seeds, called samaras, hang in long, profuse clusters and stay on the tree throughout winter. Nearly every seed is viable and will cover up a disturbed area with seedlings. The boxelder is a very prolific seeder.

Boxelder Cultivars

There are several attractive cultivars of boxelder including "Aureo-Variegata," "Flamingo," and "Auratum." The cultivar Acer negundo, "Aureo-Variegata," is noted for its leaves bordered in gold. Acer negundo, "Flamingo," has variegated leaves with pink margins and is somewhat available at local nurseries. Acer negundo, "Auratum," has abundant gold leaves but is a little harder to find.

Even though these cultivars are ornamental, they still share the original boxelder tree’s undesirable characteristics, including unattractive female fruit and breakage. The chances of the tree's early removal are still high because of its quick growth.

Problems With Boxelder

Boxelder is a rather unattractive tree when limbs break and create a landscape maintenance nightmare. The fruit droops in clusters, which some describe as looking like "dirty brown socks." And the boxelder bug makes things even worse.

The Boxelder Bug

The boxelder bug (Leptocoris trivittatus) loves the boxelder tree. This half-inch red-striped insect is a true pest during winter. Adults even multiply and invade homes near where boxelder trees grow, making it one of the most common household pests in the U.S. The bug emits a foul odor, stains fabric, and can cause asthmatic reactions. Despite the havoc it could wreak in your home, it does not harm its host tree.

Pruning Boxelder

You will have to prune this tree regularly. Boxelder branches droop as the tree grows and will require pruning if you have consistent walking and vehicular traffic under the canopy. The tree form is not particularly showy and should be grown with one single trunk to maturity. The tree is susceptible to breakage that can occur either at the crotch due to poor collar formation or where the wood itself is weak.