Boxelder maple trees, or Manitoba maple, ash-leaved maple (Acer negundo), are very odd members of the maple family. These native North American trees have long been viewed with a certain level of admiration and suspicion due to their ability to grow quickly, adapt easily, and based on other unique features. In general, this bad reputation is undeserved, as boxelders happen to be one of the most invasive species, very subject to pests and diseases. The article provides information to the readers about boxelder trees on their identification, growth habits, ecological significance, and maintenance requirements.

Identification and Characteristics

Boxelder maples are readily recognized by their compound leaves, which set them apart from most other maples that have simple leaves. Each leaf is composed of 3 to 7 leaflets, opposite on the stem. The foliage is bright green, becoming yellow in fall, although it does not have a good fall color as often as many other maples do.

The bark of the boxelder is light brown to gray; with age, it becomes deeply furrowed. The young trees have smooth bark that becomes rough with time. Boxelders produce small, greenish-yellow flowers in very early spring, well before the leaves come out. These flowers are not particularly flashy but are among the very early-season nectar sources for pollinators.

Probably one of the most distinguishing features of boxelder trees is their very prolific production of samaras, the winged seeds commonly referred to as “helicopters.” Paired samaras cover the ground beneath the tree in late summer and fall, greatly helping the tree spread quickly.

Growth Habits and Habitat

Boxelder maples are a fast-growing trees that grow from 30 to 50 feet in height and spread 20 to 35 feet. Under ideal conditions, box elder can grow 2 feet in a year. That fast growth rate makes them ideal for quick shade or shelter.

These trees are quite adaptive and they hold on to soils from very poor to compacted. They grow along rivers, floodplains, and in low-lying areas disturbed in the ground where, through their tolerance of wet conditions and poor fertility of the soil, their competitive advantage is realized. Boxelders also can tolerate urban pollution, so they become common choices for city landscapes.

Ecological Significance

Boxelder trees are extremely useful to their ecosystems. They give habitat and food to many forms of wildlife, from birds down to insects and mammals. The seeds are a food source for squirrels and birds, while many pollinators, like bees and butterflies, go after the leaves and flowers.

Moreover, boxelder trees bind the soil and prevent erosion in most instances within a riparian area. Their roots bind the soil, lessening that very impact from water runoff and help in holding both riverbanks and floodplains in good shape.

Challenges and Considerations

While boxelder trees offer some ecological value, they are considered by many to be a nuisance, especially in urban environments. In most instances, their invasion may outcompete the native vegetation and form pure stands. It is an issue especially in those areas beyond their native range.

Boxelder trees are subject to a number of pests and diseases. Perhaps the most common is the boxelder bug, which typically feeds on the seeds but frequently becomes a household nuisance, particularly during fall when it attempts to take shelter within homes. More significantly, though, boxelders are also subject to cankers and verticillium wilt, among other fungal diseases, some of which may kill or weaken them.

Another weakness of boxelder trees is that their wood is weak, thus very prone to breakage. This can be hazardous, especially in places with strong winds or heavy snows, where branches or even whole trees may crash down unexpectedly. For this reason, boxelders are normally not recommended for planting near buildings or any other structures.

Maintenance and Care

Although the boxelder trees have several weak points, proper maintenance and care can help in some of the issues. This requires regular pruning to achieve a strong structure and avoid weak, diseased branches. Prune your tree during the dormant season, which will minimize stress and reduce the chances of disease transmission.

Watering during the establishment period is very essential. Although boxelders are considered somewhat drought-tolerant, they will relish some supplemental watering during extended dry periods. Mulching around the base of the tree can help retain moisture and protect the roots from temperature extremes.

Fertilization ordinarily need not be practiced except when nutrient deficiencies are diagnosed. If necessary, use balanced, slow-release fertilizers applied in the spring.

Conclusion

Boxelder maples are a unique, very adaptable species with several positive and negative attributes. Their rapid growth, tolerance of poor conditions, and ecological benefits make them invaluable in certain settings, like erosion control or habitat restoration projects. However, their potential to be invasive, susceptibility to pests and diseases, and weak wood structure sometimes pose a challenge, especially in the urban landscape.

Any person aiming to grow boxelder trees should be aware of the pros and cons of doing so and have an established, standard practice of taking care of the trees to ensure health and safety. If well managed and taken good care of, the boxelder maples will, in most cases, remain valuable assets to the landscape.