Siberian Elm
Identification & Biology
Photo By: Lisa Scott
Siberian elm tree
Siberian elm tree
Photo By: Lisa Scott
Siberian elms
Siberian elms
Photo By: Lisa Scott
Siberian elm leaves
Siberian elm leaves
Photo By: Lisa Scott
Siberian elm immature seeds
Siberian elm immature seeds
Photo By: Lisa Scott
Siberian elm tree
Siberian elm tree
Photo By: Lisa Scott
Siberian elm trees in winter
Siberian elm trees in winter
Photo By: Lisa Scott
Young Siberian elm tree
Young Siberian elm tree
Photo By: Lisa Scott
Siberian elm tree
Siberian elm tree
Alias' :
Chinese Elm, Dwarf Elm, Littleleaf Elm
Latin Name :
Ulmus pumila
Category :
Terrestrial Plants
Description :
- Bushy, deciduous tree that grows 9-18 m tall
- Open crown and slender, spreading branches
- Bark is dark gray, ridged and furrowed
- Oval, pointed leaves with toothed margins, dark green in summer and dull yellow-green in fall
- Green, drooping flowers without petals
- Seeds in small oval-shaped seed case with wings for wind dispersal
Siberian elm was first introduced to North America in the mid-1800s for its hardiness, fast growth, and ability to thrive in varying moisture conditions. The tree is still sold commercially, but is highly invasive when it escapes cultivation. It reproduces primarily by seed, but roots can resprout when top growth is damaged. Seeds are produced early in the spring and spread by the wind, inside fruit that is winged, round and smooth that hangs in clusters. Seeds can also be transported by water and animals.
Siberian elm can sometimes be confused with other species of elms, and the native Choke Cherry (Prunus virginiana) when it is young. Siberian elm can be distinguished by its small toothed leaves (3-7 cm) that are asymmetrical at the base when they attach to the branch.
Look Alikes
Photo By: Lisa Scott
Choke Cherry Tree
Choke Cherry Tree
Habitat
Native to Northern China, eastern Siberia, Manchuria and Korea, Siberian elm can tolerate a wide range of conditions including long periods of drought, cold winters, poor soil conditions, high winds and low moisture. However, Siberian elm prefers sunny, open areas. It commonly grows on disturbed roads, moist streambanks, in pastures and rangelands, along roads and railroad rights-of-way. It will not tolerate flooding and does not often invade mature forests because of its high requirement for sunlight. In BC this invasive tree is widespread in the Southern Interior, particularly in the Okanagan.
Impact & Risks
- Siberian elm is a preferred host of the elm seed bug, an invasive insect that is a nuisance household pest; large numbers of elm seed bugs can infest homes and businesses and stink when crushed
- Siberian elm germinates readily and grows rapidly, particularly when moisture is available
- It will quickly form thickets of seedlings when soils are disturbed, such as along utility corridors, fence lines, berms, river dikes and roadsides
- It will quickly overtake native vegetation, especially shade intolerant species and reduces forage for livestock and wildlife
Prevention & Mitigation
- Do not trade or grow Siberian elm
- Regularly patrol your property for invasive trees and immediately control or remove new seedlings
- Cooperate with adjacent landowners and encourage them to prevent invasive tree spread
- Immediately re-vegetate disturbed, bare soils with a suitable seed mixture that provides dense, early colonization to prevent invasion
- Do not move contaminated soils to a new area
Treatment & Disposal
- Seedlings can be hand-pulled or dug out when the soil is moist
- Once seedlings become firmly established, the most effective control method is the cut-stump herbicide treatment during late spring; this method is both labour-intensive and expensive, but can be highly effective
- Bulldozing, mowing and brush-cutting can also be effective, but only if all re-sprouts are continually cut and removed which will likely take many consecutive years of treatment
- Girdling may also be an inexpensive and useful technique for control, which involves manually cutting away bark and cambial tissues around the trunks of trees; this control method should be undertaken using an ordinary axe in the spring when the trees are actively growing
- Chemical control is also an option; before applying herbicides, read the label for full use and precautionary instructions
- For further information on the selection and application of chemicals to protect your crop, contact AgriService BC at 1-888-221-7141 or email AgriServiceBC@gov.bc.ca
- There are currently no biocontrol agents (natural insect enemies) for Siberian elm in BC
Okanagan Distribution
Priority Level Definitions
Watch For - Poses a significant threat (very high risk) and does NOT presently occur in the region OR is relatively new to the region and is very limited in extent.
High - High risk/impact; limited population with significant potential to spread in the region.
Medium - Medium risk/impact; limited distribution – broader population distribution with potential to spread further in a region.
Low - Low risk/impact; may be widespread or not, may be of concern in specific situations with certain high values – e.g. specific agriculture crops. Some species may be treated primarily with biological control agents.
