- Siberian elm is a member of the Elm family (Ulmaceae).
- Siberian elm is a fast-growing deciduous tree reaching heights of 70 feet given the right conditions. The species’ branches are brittle and often damaged by high winds and snow. Perhaps most conspicuous in spring, this species is more easily distinguished from its close relatives when it produces little red flowers prior to leaf out.
Leaves are less than three inches long, serrate, and arranged alternately. The leaf base is generally symmetrical, unlike most elms. (2)
Flowers are small, largely inconspicuous, red, and precocious (appearing early in spring prior to leaf-out). (3)
Siberian elm fruits are dry, papery, rounded, winged samaras. (3)
Siberian elm is a fast-growing deciduous tree capable of producing thousands of seeds per individual. Particularly problematic in the Southwest and Midwest, the ecological impacts of this species are still largely unknown in the Northeast. Siberian elm is self-compatible, unlike other elms, and changes the composition of the understory layer in the habitats it invades. (1)
No biological control option is currently available.
Manual or Mechanical Control
Pulling / Digging Up: Hand pulling or digging young plants is effective, if time consuming. (8)
Mowing: Mowing, weed whacking or cutting will cause larger individuals to re-sprout. This tactic is more effective when followed up with chemical treatment. (9)
Girdling: Girdling is an effective method of control if the xylem is left intact. If cuts are made too deeply into the tree’s tissue, re-sprouting will occur. (8)
Cut and Frill: Apply a 50% solution of glyphosate or triclopyr to cuts in Siberian elm’s cambium. (10)
Prescribed Fire: Controlled burns will eliminate seedlings and small saplings but will not control larger trees. (8)
Prescribed Grazing: Siberian elm is palatable to several grazers, however, little is known about the efficacy of grazing expressly to control this species. (9)
Soil Tilling: No information available
Mulching: No information available
Solarization: Not applicable
Hot Foam Spray: No information available
The pesticide application rates and usage herein are recommendations based on research and interviews with land managers. When considering the use of pesticides, it is your responsibility to fully understand the laws, regulations and best practices required to apply pesticides in a responsible manner. At times, the pest you seek to treat may not be on a pesticide label, requiring a 2ee exemption from NYSDEC. Always thoroughly read the label of any pesticide and consult the NYSDEC or a licensed pesticide applicator with questions.
Foliar Spray: A 1.5% solution of glyphosate, triclopyr, or Imazapyr is effective. Always read all instructions on the label. (8)
Cut Stump: A 20% solution of glyphosate applied immediately to cut stems is effective in controlling this species. (9)
Basal Bark: A 20% solution of triclopyr is effective at treating smaller trees of approximately 2 to 3 inches in diameter when applied from early fall through winter. (9)
Stem Injection: No information available
Pre-Emergent Spray: No information available
As with any other invasive infestation complex, large stands of Siberian elm are best managed via a combination of mechanical and chemical means. Larger individuals should be treated with a cut stump or basal bark herbicide application, while small individuals can be pulled or cut. All managed infestations should be monitored for at least three years to ensure exhaustion of the seed bank and to monitor for any re-sprouting (4). Any new seedlings can be hand pulled. New sprouts must be treated with foliar spray or continually re-cut.
Post treatment monitoring
Controlled populations should be revisited at least two times a season for at least three years to ensure exhaustion of the seed bank and to check no re-sprouting has occurred.
Mowed, cut, or pulled Siberian elm can be composted or chipped so long as management occurred prior to fruiting.
- Interview with Trillium Invasive Species Management INC