Once highly prized shade trees, elms have fallen on hard times. Dutch elm disease (spread by a bark beetle) has killed millions of American elms in North America and can attack most other elm species. Many of the larger elms are appealing fare for various types of aphids, beetles, leafhoppers, and scale, making them time-consuming to care for, messy, or both. Elms have other problems not related to pests. They have aggressive, shallow root systems, so you’ll have trouble growing other plants beneath them. Many produce suckers; branch crotches are often narrow, splitting easily in storms. Still, elms are widely planted, and researchers continue to devote much effort to finding disease-resistant varieties. Elms tolerate a wide range of soils. Poor yellow fall color except as noted.Ulmus americana
Native to eastern North America. This majestic, arching deciduous tree once graced lawns and streets throughout its range, but it has been decimated by Dutch elm disease. Fast growth to 100 ft. or taller with nearly equal—sometimes greater—spread. Main branches are upright, outer ones pendulous. Rough-surfaced, 3–6-in.-long, toothed dark green leaves; great variation in shade of yellow fall color. Leafs out very late where winters are mild. Pale green, papery seeds make a mess in spring. Disease-resistant varieties include ‘Princeton’ (upright, to 65 ft. tall), ‘Valley Forge’ (vase-shaped, to 70 ft. tall), and ‘Jefferson’ (vase-shaped, to 70 ft. tall).
These big-leafed woodland plants thrive in the rich organic soil under tall trees and shrubs. They gro...
Biennial or short-lived perennial. From southern Europe and northwestern Africa. Soft, scallop-edged, ...
Native to the eastern half of North America, extending southwest to Arizona. The species is rarely off...