Invasive Plants of the Illinois River Watershed

Our region has several invasive species, some of which outcompete native species of plants and some which have largely been able to integrate with our region’s vegetation and ecology. We encourage the public to be aware of the most important species which require active monitoring and a regionally coordinated approach to management.

Our friends at the Watershed Conservation Resource Center (WCRC) have put together this handy digital guide to invasive plants of Northwest Arkansas (also relevant in much of Northeast Oklahoma). Download a copy of the guide on Invasive Plants of Northwest Arkansas.

The City of Fayetteville has a handy educational packet on Invasive Plant Species and native alternatives for landscaping.

Highly Invasive Species in the Watershed

  • Bush Honeysuckle (Lonicera maackii)

    STATUS Invasive ornamental hedge introduced from China.

    DISTRIBUTION Widely present in southern US. Invades forest understory, fencerows, along streams, and rights-of-way.

    IMPACT Aggressive, shade-tolerant shrub that forms dense thickets, often creating monoculture preventing forest regeneration, especially in urban forest near where plants escaped or were planted. Poor wildlife food source. May contribute to increased tick populations.

    IDENTIFICATION Multi-stemmed upright shrub, bark light brown with striations, sometimes hollow. Opposite leaves ovate to oblong. Distinct sweet smelling white and yellow flowers in spring and summer produce glossy red berries when ripe.

    CONTROL Remove entire plant. Cut to stump in fall and apply 50% glyphosate immediately after cutting. Repeat seasonally until suckers are no longer present.

  • Chinese Privet (Ligustrum sinense)

    STATUS Invasive ornamental hedge introduced from China and Europe c.1852.

    One of the most common and troublesome invasive plants.

    DISTRIBUTION Widely present in southern US. Invades forest understory, fencerows, along streams, and rights-of-way.

    IMPACT Aggressive, shade-tolerant shrub that forms dense thickets, often creating monoculture preventing forest regeneration, especially in urban forest near where plants escaped or were planted. Poor wildlife food source.

    IDENTIFICATION Multi-stemmed shrub of the Olive family with opposite, glossy, oval, green leaves. Fragrant white flowers April to June produce abundant, green berry-like drupes turning dark purple. Propagates through seed spread by animals and is a prolific suckering plant.

    CONTROL Remove entire plant if possible. Cut to stump in fall and apply 50% glyphosate immediately after cutting. Repeat seasonally.

  • Creeping Euonymus (Euonymus fortunei)

    STATUS Introduced from Asia as ornamental ground cover in early 1900s. Resembles periwinkle (Vinca). Highly invasive in Northwest Arkansas’ urban forests, along trails, streams, forest edges and understories.

    DISTRIBUTION Eastern and southern US.

    IMPACT Adaptable, aggressive, vine that forms dense groundcover or climbs structures including trees, which may be choked. The vine will completely cover large areas of forest floor and out-compete native plants. Fruit spread by birds. Weight can eventually topple trees and fences.

    IDENTIFICATION Evergreen woody vine forming numerous clinging stems. Opposite, oval, glossy green leaves with prominent veins. Inconspicuous flowers produce small red capsules at the end of y-shaped stems that split, exposing seeds.

    CONTROL Cut stump and apply appropriate herbicide. Late winter treatment will avoid non-target damage. Repeated treatments likely. Hand pull small infestations.

    Caution: wintercreeper attached to a tree may transfer herbicide to the tree.