Leafy Spurge: The Explosive Threat Spreading Across the Land
Tuesday, August 12, 2025
Every year, leafy spurge claims more land, creeping in quietly and establishing itself with alarming resilience. Can you recognize this infamous invader? With its small yellow-green flowers and smooth stems that exude a milky latex when broken, leafy spurge might look harmless at first glance. But beneath that modest appearance lies a formidable threat armed with powerful survival tactics.
In Alberta, leafy spurge is designated as noxious under the Weed Control Act, meaning landowners are legally required to control and prevent its spread. This aggressive perennial is not only a threat to native ecosystems but also to agriculture, rangelands, and wildlife habitats.
Growth Habitat & Reproduction
Leafy spurge’s greatest strength lies underground—its root system can extend up to 15 feet wide and dive 26 feet deep. Even more troubling, these roots release chemicals that inhibit the growth of neighboring plants, giving leafy spurge a competitive edge. The plant itself is toxic causing skin irritations in both humans and cattle. Should cattle ingest it they may experience digestive issues and possible death.
This noxious weed can regenerate new shoots from root fragments buried as deep as three feet, making mechanical removal challenging. It also produces explosive seed pods that launch seeds several feet away, helping it spread rapidly across the landscape.
Prevention & Control
The best defense against leafy spurge is prevention, combined with early detection and rapid response. It is always important to avoid purchasing hay from infested areas or better yet, opt for certified weed free forage. If moving livestock from a known infestation area, isolate animals for a period beforehand (ideally one week) to prevent seed dispersal. Routinely monitor susceptible habitats and act quickly at the first sign of new growth.
If an infestation takes hold, be prepared for a prolonged battle. Young plants can be hand-pulled with gloves to prevent skin irritation. Routine mowing and spot applications of herbicide can also help with control. Herbicides such as 2,4-D and Glyphosate are effective – just be sure to read and follow label instructions closely. Leafy spurge also has a hidden weakness: it does not tolerate frequent soil disturbance. Regular tilling can damage its root system over time; however, use caution, as bare soil can create an opportunity for other invasive species to establish.
Biological controls, such as imported beetle species, are available and can help reduce leafy spurge populations. Goats offer another unique option as they can graze leafy spurge without harm. However, this is not a permanent solution as the weed can resurface once grazing pressure is removed.
The most effective control strategy is to combine multiple methods—mechanical, chemical, biological, and cultural—to launch a coordinated, multi-pronged attack. This integrated approach is the best way to turn the tide against leafy spurge.
Dig Deeper
For more information on invasive species and native plants, please see the resources listed below.
Weed Identification
Native Species
Biocontrol Agents
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Agriculture