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Invasive Species: Shrubs

Invasive Shrubs

Species that are not native and also have the potential to harm human health or to harm natural, agricultural or silvicultural resources can be listed as prohibited or restricted by the State of Michigan. If a species is prohibited or restricted, it is unlawful to possess, introduce, import, sell or offer that species for sale as a live organism, except under certain circumstances.

Autumn Olive

(Elaeagnus umbellata)

Restricted in Michigan

Autumn olive is a deciduous shrub that can grow to 20 feet high. Its leaves are bright green on top and distinctively silver underneath. Spring-blooming cream or yellow flowers have a strong fragrance and abundant red berries are lightly speckled and easily seen in the fall. The flowers bloom in August and September in Michigan.

More information: Autumn olive

Common Buckthorn

(Rhamnus cathartica)

Common buckthorn is a shrub or small tree that can grow to 25 feet. It has oval, slightly toothed leaves. Twigs often have a single, sharp thorn at their tips.

More information: Common buckthorn

Giant Knotweed

Polygonum sachalinensis (Fallopia sachalinensis)

Giant knotweed is a bamboo-like shrub that can grow up to 12 feet tall. It has white, spike-like flowers and long, heart-shaped leaves.

More information: Giant knotweed

Glossy Buckthorn

(Rhamnus frangula or Frangula alnus)

Glossy buckthorn is a shrub or small tree with simple, shiny leaves and pea-sized red to purple fruit. Despite the name, glossy buckthorn has no thorns. 

More information: Glossy buckthorn

Japanese Barberry

(Berberis thunbergii)

Japanese barberry is a spiny, deciduous shrub usually 1-2 feet, but can grow up to 6 feet in height. It has small, oval-shaped green leaves with smooth edges. Leaves turn red in the fall.

More information: Japanese barberry

Japanese Knotweed

(Fallopia japonica)

Prohibited in Michigan

Japanese knotweed is a perennial shrub that can grow from 3 - 10 feet high. It has hollow stalks that are persistent through the winter and look similar to bamboo. The stems have a fine white coating that rubs off easily. The flowers are arranged in spikes near the end of the stems that are small, numerous and creamy white in color. Flowers bloom in August and September in Michigan.

More information: Japanese knotweed

Multiflora Rose

(Rosa multiflora)

Multiflora rose is a multi-stemmed shrub growing to 15 feet. Flowers are small, white to pink, and have a strong fragrance. Bright-red rose hips develop in the fall and persist into winter.

More information: Multiflora rose