Kamloops, B.C., working to remove invasive Russian olive trees — but it could take decades

CBC News

· Posted: Nov 01, 2025 9:00 AM EDT | Last Updated: November 1

Russian olive trees — sometimes known arsenic metallic berry oregon oleaster —  are small, ornamental plants with silvery leaves and achromatic bark, and tiny yellowish flowers and metallic effect that look similar miniature olives. They’re pretty, but they’re a problem. 

The taxon is invasive successful B.C., having been brought to the state from its autochthonal scope successful Russia and different parts of Asia, according to the Invasive Species Council of B.C. And that’s wherefore immoderate communities, similar Kamloops, are looking to get escaped of them. 

Russian olive is simply a hardy works that tin past successful adust conditions and acold temperatures, making it cleanable for a clime similar that of Kamloops, a semi-arid, desert-like metropolis successful B.C.’s Interior. 

They instrumentality successful much h2o than astir plants successful areas wherever the ungraded is dry, which means they tin outgrow autochthonal plants, the invasive taxon assembly says. 

“Whenever you person a non-native species, there's immoderate that are reasonably assertive, assertive and those are the ones that we are acrophobic about,” assembly enforcement manager Gail Wallin said. 

WATCH | City of Kamloops moving to get escaped of Russian olive trees:

She said Russian olive are “huge competitors” for water. 

“In a clip erstwhile we're truly acrophobic astir h2o and h2o availability for our autochthonal taxon and for habitats, that's a existent concern.”

But getting escaped of them isn’t truthful easy. Because they person a beardown basal strategy and volition turn backmost if each spot of works isn’t removed, other attraction has to beryllium taken, according to Wallin. 

In Kamloops, the metropolis is taking a antithetic approach. 

Instead of pulling up trees and risking not getting the roots, oregon spraying them with pesticides that could beryllium harmful to the ecosystem, the metropolis is utilizing biologic controls — bugs. 

Aceria angustifoliae are tiny mites recovered successful Europe and Asia, according to Kirsten Wourms, the unit person of earthy resources for the City of Kamloops.

She said the mites impact the flowers, the fruits and caller young shoots of the trees truthful that they cannot reproduce.

“Over time, we're really looking astatine the Russian olive colonisation decreasing,” Wourms said.

But, she said, the process could instrumentality anyplace from 20 to 50 years.

Kirsten Wourms, unit person for earthy resources with the City of Kamloops, said it could instrumentality decades for the Russian olive histrion populations to alteration — but utilizing biologic controls is little harmful to different species, she added. (Jenifer Norwell/CBC)

Moving dilatory isn't each bad, though. Wourms said it volition springiness birds, insects and different animals that person travel to trust connected Russian olive trees clip to set and find alternate nutrient oregon shelter.

“One of the biggest lovers of Russian olive are the bears,” Wourms said. “They travel successful and devour the effect successful the fall, assistance to fatten them up. So galore pollinators usage them.”

The task is successful conjunction with the Canadian Food Inspection Agency (CFIA), Wourms said, which has tested the mites to marque definite they won’t harm different taxon successful the area.

Education program

The Invasive Species Council of B.C. is ever moving to amended British Columbians astir plants, insects and animals that are harming autochthonal species.

Wallin said they’ve been moving with section retailers to get them to halt selling invasive plants, and immoderate section governments prohibition definite species, though Russian olive has not yet been banned by astir municipalities, she added.  

The assembly runs a programme called PlantWise that aims to marque B.C. invasive species-free. They promote radical to larn astir the plants successful their yards and communities, and to get escaped of immoderate invasive ones responsibly. 

“We tin each marque a large difference,” Wallin said.