12 Invasive Shrubs That Can Damage Native Ecosystems

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Invasive shrubs are non-native plants of foreign origin that can establish and grow quickly, sometimes out-competing native species. When exotic species are introduced, they can create trouble in the new ecosystem by disrupting nutrient cycles and pH levels in the soil, which can influence herbivores and minimize the biodiversity of a particular region.

Some of the most damaging invasive shrubs include.

Japanese Barberry (Berberis thunbergii)

Photo Credit: Agnieszka Kwiecien, Nova/Wikimedia Commons

This shrub is from Japan but has been widely naturalized across the continental United States. It creates a dense thicket which forms thickets that can sprawl over native vegetation, and it has no effective natural enemies to control its spread. Barberry also generates seeds that are food for birds, enabling them to carry and sow it on fresh land.

Autumn Olive (Elaeagnus umbellata)

Originally planted as an erosion-control plant and a wildlife food source, the shrub spread quickly through seed dispersal and formed dense thickets that choked out native species. Autumn olives are also nitrogen fixers, altering the nutrient availability in the soil to favor them over other plants.

Russian Olive (Elaeagnus angustifolia)

Photo Credit: Robert Flogaus-Faust/Wikimedia Commons

The shrub was once marketed as decorative but has established itself in natural riparian systems, where it is now an unwanted invasive species. It competes with native vegetation and changes stream flow patterns, unnecessarily using up water resources that other plants and animals need. Birds also spread it to other worthy locations.

European Buckthorn (Rhamnus cathartic)

Photo Credit:, Krzysztof Ziarnek, Kenraiz/Wikimedia Commons

Native to Europe, this plant was initially planted as a hedge and for erosion control but has become one of the most invasive species in North America. It is a large, high-quality shrub that out-competes the native flora for resources and suppresses the re-growth of other species. It also produces chemicals in its leaves that will kill other plants if they grow near it.

Burning Bush (Euonymus alatus)

Photo Credit: Chris Barton, Gif Absarnt/Wikimedia Commons

What was once an innocent and domesticated winged euonymus shrub has become a widespread invasive species in North America. It outcompetes native vegetation and alters soil pH levels, making it difficult for other local plants to grow. Birds carry their seeds away from the plant to assist in spreading shrubs.

Common Buckthorn (Rhamnus cathartic)

Common buckthorn is a shrub from Europe that has been introduced to North America. Its close-packed thickets squeeze out native plants, and the plant adjusts soil chemistry bred to enable its own available species. The plant is highly toxic to humans, and its berries are harmful to birds, which have declined dramatically.

Multiflora Rose (Rosa multiflora)

According to a publication by IPM Images, Multiflora rose was imported as rootstock for rose grafting but is now well-entrenched in the eastern U.S. It competes well with native vegetation and develops a dense, impenetrable canopy that is hard to maintain. Given its thorns, the plant is also a menace to humans and animals.

Chinese Privet (Ligustrum sinense)

The shrub is southern-invasive in the Southeastern U.S. and is originally from Asia. It blocks other plants from sprouting and destroys them with its thick shoots. It spreads aggressively through seed and is nearly impossible to control.

Tamarisk (Tamarix spp.)

Photo Credit: Forest and Kim Starr/Wikimedia Commons

This introduced Eurasian shrub (a common plant in North America, where it is established because of its use in ornamental plantings or for erosion control), which invades riparian areas and displaces native plants while changing stream flow patterns. Also, it is salt-impervious, so other plants do not grow nearby.

Himalayan Blackberry (Rubus armeniacus)

An Oregon State University study states that this plant is common throughout the Pacific Northwest in the USA and was originally introduced for food. It spreads rapidly and overtakes native plants, creating a monoculture that changes soil chemistry or makes conditions unsuitable for many other plant species. Even the thorns of this deadly plant are not good for humans and animals.

Japanese Honeysuckle (Lonicera japonica)

Photo Credit: SB_Johnny/Wikimedia Commons

Originating from East Asia, this woody plant was initially introduced to North America as an ornamental and for erosion control applications. It can cover the ground, crowding out native species and rendering soil chemistry with particles that prevent most other plants from growing. The vines can even cover trees and shrubs.

Tree of Heaven (Ailanthus altissima)

Photo Credit: Luis Fernandez Garcia/Wikimedia Commons

Originally introduced in China as an ornamental tree, it has escaped and has become highly invasive in human-modified landscapes. It outcompetes natural species, and its leaves are toxic, capable of preventing other plant life from sprouting into whole orders such that flora is left dead. This herb is fast-growing and can reproduce vegetatively by root sprouts, so it can be challenging to control.

Disclaimer: This list is solely the author’s opinion based on research and publicly available information.