Invasive Knotweed Regional Reporting System launched in the Capital Region

Protect Against Invasive Species - English Holly

Why control English holly

Holly (1) English holly grows quickly, forming dense thickets in forests.  Tall holly shrubs cast deep shade on understory plants, making it difficult for native plants to compete for light, water and nutrients.   Some plant surveys in Washington are finding English holly among the most frequent non-native species in forest understories, which could allow this invasive species to replace aging deciduous forests instead of native coniferous forest ecosystems.

What you can do to help

Eliminate the source

Keep English holly out of your garden.  Gardeners struggle to keep holly within the confines of their gardens.  Birds easily disperse the eye-catching red berries that hold holly seeds, spreading them deep into our neighbouring forests.  Holly also escapes by suckering and layering.  The best strategy to keep holly out of our forests and native habitat is by keeping it out of your garden.

Pull or cut

Hand-pull small seedlings when the soil is moist.  Cut larger trees at ground level and regularly monitor the area for re-sprouting either at the stump or through suckers nearby.  Eventually, diligent cutting will kill the root system.  Mature trees have deep and extensive roots making digging labour-intensive and highly disruptive to surrounding soil.
Holly (2)

Dispose of holly seeds

Holly berries should be placed in the garbage to make sure they don't sprout elsewhere.  Holly stems and leaves can be composted, but watch they don't sprout roots.

Restore the site

Removing holly can leave gaps in a forest - future habitat for any number of deserving native species.  Alternative plants that you can plant include tall Oregon grape, Indian plum, and red elderberry.

For more information and helpful tips

Contact your local conservancy to see if they can help you find the most effective way to remove English holly from your land.  For more information about English holly and best practices for removing this plant, visit:

Page last updated: 01/08/18
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