
English Laurel
Botanical Name:
Prunus laurocerasus
Monitor List
General
- Other common names are cherry laurel, and common laurel.
- Native to southwestern Asia and southeastern Europe.
- This plant is toxic to humans and may be fatal if eaten; poisonous parts include wilted leaves, stems, and seeds.
- There are currently no regulations or limits on the sale or use of English laurel in Washington.
- Although it is not a state listed noxious weed, control is recommenced and new plantings are discouraged especially where it could impact nearby forests.
- A 2006 study on Seattle’s urban forests, found English laurel was the second most common invasive tree species, occurring on 67% of study plots. English holly was the most common invasive tree found.
- English laurel out-competes native forest species such as tree seedlings and native shrubs, replacing native canopy trees over time. Fast growing and tolerant of a wide range of conditions, it has the potential to be a serious threat to native forest lands in the Hood Canal watershed.
Identification
- Large, spreading, evergreen shrub, growing to around 10 to 30 feet tall. Grows as either a single-trunk tree or a multi-stemmed shrub.
- Leaves are dark to medium green on top and paler green on the underside. Leaves are leathery with finely toothed edges, alternately arranged, 2 to 6 inches long, obovate to oblong in shape, and have two glands at the base of the blade just above the petiole.
- Mature stems are smooth reddish brown to dark brown; new stems are green.
- Flowers are small (1 cm wide), white, and resemble cherry blossoms. They have 5 petals, and many fragrant yellow stamens. Flowers appear in upright racemes, 2-5 inches long. Blooming occurs from April to May.
- Fruits are purplish-black drupes, ½ inch long, appear in clusters.
Habitat
- Grows in sun to shade, moist to dry soils, but does best in moist, well-drained soils.
- Common residential landscape plant used for privacy hedge rows.
- Often escapes into adjacent natural areas and out competes native understory shrubs and tree seedlings. Commonly found in urban forests, and parks but is also found escaping into more remote areas.
Reproduction and Spread
- Much like English holly, English laurel reproduces by seed and by vegetative means.
- Birds and possibly other animals eat the fruit and spread the seeds into adjacent and remote natural areas.
- Plants spread laterally by layering, growing roots where stems touch the ground. Cuttings can also form roots and create new infestations when dumped as yard waste in backyards ravines or along roadsides.
Control
- Small plants can be dug up when soil is moist.
- For larger plants, cut stems or trunk as low to the ground as possible using a chainsaw or handsaw. Plants will resprout, so follow up treatments will be necessary.
- Cut stems can be chipped and used as mulch. You can also cut, pile and leave on site to decompose. Monitor for stem rooting if left on moist soil.
- Burning English laurel should be done with caution as smoke may cause adverse health effects, due to the toxins in the plant.
Chemical Control
- Foliar application is not recommended due to English laurels thick, waxy leaves that prevent the chemicals from being absorbed.
- EZ-Ject Lance Method: injects a small metal capsule of herbicide into the cambium layer and kills the roots, stems and foliage. Make sure to use the copperhead imazapyr herbicide shells as glyphosate may not be effective against laurel.
- Cut-Stump Method: Cut the plant as close to the ground as possible and apply concentrated herbicide immediately to the cut portion. Apply herbicide to the whole cut surface but specifically focus on applying to the outer ring or cambium layer which will transport the herbicide to the root system.
- Hack and Squirt Method: Using an arborist chainsaw, hand saw, hatchet, or similar tool, cut downward-angled incisions, about 2 to 4 inches long and 1 to 2 inches apart. Make sure all cuts are below the last live branch, around the trunk. Cuts must penetrate through the bark into the living tissue and produce a cupping effect to hold the herbicide. Using a chemical resistant spray bottle or wash bottle, carefully apply concentrated herbicide into the cuts.
- Herbicides containing the following active ingredient are effective on English laurel:
- Imazapyr
- Apply during fall or spring.
- Cut stump treatment, apply undiluted solution.
- Hack and squirt, apply a 50% solution at intervals of 3-4 inches.
- Inject EZ-ject copperhead, insert 1 shell every 2-3 inches around the tree. Results will be visible within 6 months.
- Do not exceed 96 fluid ounces of concentrated product per acre.
- Triclopyr
- Apply during fall or spring.
- Cut-stump treatment, undiluted solution.
- Hack and squirt, apply 1 ml of 50 to 100% solution at intervals of 3 to 4 inches.
- Imazapyr