Integrated Pest Management

Siberian Elm

Ulmus pumila

Siberian elm

Siberian elm seedlings (John M. Randall, The Nature Conservancy, Bugwood.org)

Siberian elm

Mature Siberian elm (John M. Randall, The Nature Conservancy, Bugwood.org)

Siberian elm

Siberian elm leaves (Steve Dewey, Utah State University, Bugwood.org)

Description

  • tree (up to 70 feet) with elliptical-shaped green leaves; leaves are arranged alternately on stems
  • leaves have serrated margins and pointed tips; leaf veins have a distinctive fishbone pattern
  • flowers are green, form in clusters (6 to 15) and are 3/16 inch long
  • seeds are housed in flat, coin-shaped fruit equipped with a papery wing that turns from green to straw color as it matures

Location

  • commonly grows in planting beds and in and amongst other trees, shrubs, perennials and along fences

Life Cycle

  • long-living perennial (deciduous tree) that flowers from early to mid-spring
  • flowers are produced before leaves expand; seed production immediately follows leaf emergence
  • seeds ripen by late spring and can germinate immediately; leaves turn yellow in fall

IPM Recommendations

  • Hand-pull elm seedlings in planting beds prior to seed maturation and manually remove underground structures to prevent re-sprouting.
  • Apply a mulch layer 3 inches deep on planting beds to reduce seed germination.
  • For control of small plants, spot treat with appropriate post-emergent systemic herbicide. For control of larger plants, cut stem or trunk and immediately paint the outside circumference (just inside bark) with concentrated systemic post-emergent herbicide.
  • Fall (close to fall color and leaf drop) is an effective time for chemical control.