It lurks within the dark and shadowy places in a forest understory, but also boldly bathes in sun along a property’s road edge. The quality of the soil is rarely a limiting factor to its growth. Perennially green and glossy, this shrub is considered attractive. Its toxicity, however, makes news headlines. And, its invasive nature destroys vulnerable native plants in its path. Let’s get to know — better — Daphne laureola.

Also known as spurge-laurel (although it is neither a spurge nor a laurel) it is slow to establish but quick to expand, making its invasion of Mayne Island quite effective. Widespread acceptance and spread, paired with a lack of public knowledge, has led to an invasion of Mayne Island that in places rivals that of Scotch broom.

Identifying the Invasive

Daphne growing on Mayne Island. Photo by Shannon Miller.

Formal introductions of Daphne laureola were made to North America as an ornamental plant from Europe in the early 1900s.

The plant begins as a single stem and grows thick, green, shiny leaves similar in texture to a rhododendron — giving it a glossy appeal; perhaps this is why it continues to be sold as an “attractive” plant for gardeners. It grows to 1.5 m in height in either a single stem or multi-branching habit, flowering in the spring and bearing toxic black berries in the summer.

When left to flourish, it takes over native vegetation, forming dense thickets in the forest understory.

The daphne resume includes these impressive invasive skills: a single plant can turn into a patch of thousands of stems; its extremely resilient growth re-sprouts after cutting; it easily spreads to neighbouring properties; it crowds outs and displaces native species; it is very resistant to deer browse; and it thrives in the understory of Pacific Northwest forests.

Toxic Nature

Daphne is toxic to the touch, to inhale, and to ingest. Cutting the stems results in a noxious gas. Touching them without gloves can result in an itchy rash. It’s listed as a poisonous plant by the Canadian Poisonous Plants Information System, which lists nausea, swelling of the tongue, and coma as potential outcomes of contact with the plant. If the berries are ingested they can lead to death — although not for birds, who ingest them despite the toxicity, and then readily disperse the seeds.

Managing an Outbreak

The most effective management method is manual removal — which requires the proper equipment, including gloves, goggles or face shield, and clothing that protects the arms and legs. If controlling plants for extended periods, a HEPA filter face mask or respirator is needed.

It won’t re-sprout from roots, but readily re-sprouts from stem tissue, so destroying one or two grown stems can cause 50 sprouts to appear. To prevent re-sprouting, the plant needs to be cut below the root collar, the place where the stem becomes root. If you can’t identify the root collar, just cut below the first root branch.

Assaults must remain manual. However cathartic, any use of brush saws, weed whackers, or full-on attacks of a chainsaw will cause the toxic sap to volatilize, leading to respiratory problems.

The young plants (less than 15cm tall) are easily ripped from the ground with the root intact and without soil disturbance, especially when the soil is moist.

Ensure your daphne casualties are not burned (this is hazardous to your health) but rather piled away from garden compost in their own pile of doom, and left to decompose. Or gather and seal it in a contractor’s garbage bag so the seeds do not continue to spread.

Since daphne plants live longer than 40 years, prepare for an extended battle.


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