Answer: Everything you have heard about Acer negundo, the box elder is probably true. It's messy, attracts insects, is brittle, short-lived and grows in cracks in the sidewalk. It's a plant only a mother could love.
Yet, some of the most respected nurseries are boldly offering it as a proud street tree. What's going on here? Cultivars, that's what. The Acer negundo species with a trash-tree reputation has little in common with some of its selections, such as 'Variegatum,' 'Flamingo' and 'Sensation,' according to Keith Warren, horticulturist for J. Frank Schmidt & Son Co. of Boring, Ore. These cultivated varieties of the neighborhood box elder that blows apart in a windstorm and produces progeny in everyone's yards are slower growing, have attractive foliage and produce no seed. 'Flamingo' and 'Sensation' are male clones; 'Variegatum' is a sterile female. Their compact growth habit modifies the characteristic brittle limbs common to the species. And 'Sensation,' Warren said, holds no interest to box elder bugs (which seem to prefer female-flowering trees), those orange-and-black critters that litter sidewalks, drop into your hairdo and emit a disagreeable odor.
Among these cultivars, Warren said, you'll find "a lot of refinement from the original," not only in limb strength but also in foliage. 'Flamingo' is multicolored, with variegated white-and-green leaves that emerge with a distinct pink tone in spring. Fall color is an attractive reddish tint. 'Variegatum' has creamy white and green leaves, and 'Sensation' greets the spring with soft coppery-red foliage that matures to medium green, retaining a slightly reddish tone beneath the green in summer months, then becoming bright red in the fall.
These cultivars grow much more slowly than the species, and do not reach its great height, either. None of them will get much more than 30 feet tall, which allows them to be used comfortably in many street locations (common in Portland, Ore., Warren said) and small residential landscapes. Schmidt lists all as hardy to USDA Hardiness Zone 5.
Hope this information is helpful!
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