Appearance
Ulmus pumila is a deciduous tree up to 70 ft. (21.3 m) in height. The crown is open and rounded with slender, spreading branches. The bark is light-gray with irregular furrows.

Foliage
The leaves are less than 3 in. (7.6 cm) long, alternate, simple, singly-serrate, and dark-green in color. Unlike most elms, the leaf base is usually symmetrical.

Flowers
Green, inconspicuous, apetalous (without petals) flowers develop, in drooping clusters, in the spring.

Fruit
Fruits are flat, circular and 0.5 in. (1.3 cm) wide and each contains a single seed.

Ecological Threat
Ulmus pumila invades pastures, road-sides, and prairies throughout the Midwest and Great Plains regions of the United States. The trees are very drought and cold resistant allowing them to grow in areas where other trees cannot. The abundant, wind-dispersed seeds allow this plant to spread rapidly. It forms dense thickets that close open areas and displace native vegetation, thereby reducing forage for wild animals and livestock. Ulmus pumila is native to northern Asia and was first introduced into North America in the 1860s. It has been planted throughout the Midwest and Great Plains for windbreaks and lumber.

Resources

• Plant Guide - USDA NRCS National Plant Data Center
• Weeds Gone Wild: Alien Plant Invaders of Natural Areas - Plant Conservation Alliance
• Weed of the Week - USDA Forest Service
• Weed Field Guide - USDA Forest Service

Selected Images

Maps

Invasive Listing Sources

• Arizona Noxious Weeds
• City of Ann Arbor Michigan Parks and Recreation
• Colorado Noxious Weeds
• Commonwealth of Pennsylvania, Department of Conservation and Natural Resources, 1994.
• Hoffman, R. & K. Kearns, Eds. 1997. Wisconsin manual of control recommendations for ecologically invasive plants. Wisconsin Dept. Natural Resources, Bureau of Endangered Resources. Madison, Wisconsin. 102pp.
• Indiana Invasive Species Council - Invasive Plant List
• Invasive Plant Association of Wisconsin
• Invasive Plant Species of West Virginia
• Iowa Forest Invasive Plants
• Jil M. Swearingen, Survey of invasive plants occurring on National Park Service lands, 2000-2007
• John Randall, The Nature Conservancy, Survey of TNC Preserves, 1995.
• Kentucky Exotic Pest Plant Council - Significant Threat
• Maine Invasive Plants
• Maryland Cooperative Extension Service.  2003. Invasive Plant Control in Maryland. Home and Garden Information Center, Home and Garden Mimeo HG88. 4 pp.
• National Park Service, Mid-Atlantic Exotic Plant Management Team Invasive Plant List
• New Hampshire Invasive Species Committee. 2005. Guide to Invasive Upland Plant Species in New Hampshire. New Hampshire Department of Agriculture,  Markets and Food Plant Industry Division and New Hampshire Invasive Species Committee.
• New Jersey Invasive Species Strike Team 2017 Invasive Species List
• New Mexico Noxious Weeds
• Non-Native Invasive Plants of Arlington County, Virginia
• Non-Native Invasive Plants of the City of Alexandria, Virginia
• Nonnative Invasive Species in Southern Forest and Grassland Ecosystems
• Ohio Invasive Species Council
• Pennsylvania Department of Conservation and Natural Resources Invasive Plants
• Reichard, Sarah. 1994.  Assessing the potential of invasiveness in woody plants introduced in North America. University of Washington Ph.D. dissertation.
• South Carolina Invasive Pest Council
• Virginia Invasive Plant Species List
• WeedUS - Database of Plants Invading Natural Areas in the United States
• West Virginia Invasive Species Strategic Plan and Volunteer Guidelines 2014
• West Virginia Native Plant Society, Flora West Virginia Project, and West Virginia Curatorial Database System, September 3, 1999
• Wisconsin Noxious Weeds
• Wisconsin's Invasive species rule – NR 40

References