Common Woody Invasive Plants That Threaten Your Landscape

Woody invasive plants can quickly take over landscapes, woodlands, and open areas, crowding out native species and disrupting local ecosystems. Left unmanaged, these aggressive shrubs and trees reduce biodiversity, damage soil health, and make your property harder to maintain.

Understanding which woody invasives are common in southeastern Wisconsin, how to identify them, and how to manage them in essential to protecting your landscape and maintaining a healthy, vibrant property.

Bush Honeysuckles (Amur, Tartarian, Morrow's)

Commonly affects: Wooded edges, open fields, residential landscapes

Bush Honeysuckles leaf out early in spring and form dense thickets that shade out native plants. Birds spread the bright red berries widely, allowing the shrubs to invade natural areas and yards alike.

Signs to watch for:

• Early leaf-out before most native shrubs

• Bright red or orange berries in fall

• Dense, tangled growth forming thick understory

Common Buckthorn (Glossy & Common Buckthorn)

Commonly affects: Forest edges, pastures, disturbed sites

Buckthorn is one of Wisconsin's most aggressive woody invasives. It outcompetes native trees and shrubs, alters soil chemistry, and serves as a host for pests and diseases that can affect other plants.

Signs to watch for:

• Glossy, dark green leaves that stay on branches late into fall

• Thorns on branches

• Small black berries in late summer and fall

Japanese Barberry

Commonly affects: Forests understory, hedgerows, residential landscaping

Japanese Barberry is a compact, thorny shrub that spreads quickly and forms dense thickets. Its berries are eaten by birds, which help it spread further. It also creates favorable conditions for ticks.

Signs to watch for:

• Small, oval leaves, often reddish in color

• Sharp thorns along branches

• Bright red berries in late summer and fall

Multiflora Rose

Commonly affects: Pastures, roadsides, open fields

Multiflora Rose is a thorny, sprawling shrub that forms dense thickets. It outcompetes grasses and native shrubs, and its rapid growth makes mowing and grazing difficult.

Signs to watch for:

• Clusters of small white flowers in spring

• Long, arching canes with sharp thorns

• Dense, tangled growth that forms impenetrable patches

Round-Leaf Bittersweet

Commonly affects: Forest edges, open fields, hedgerows

Round-Leaf Bittersweet is a vine-like shrub that climbs over trees and shrubs, strangling them and blocking sunlight. It spreads rapidly and produced abundant orange berries.

Signs to watch for:

• Round, glossy leaves

• Orange berries in fall

• Twining stems climbing over other vegetation

Black Locust

Commonly affects: Open fields, disturbed areas, roadsides

Black Locust is a fast-growing tree that spreads aggressively through root suckers. Its dense growth crowds out native plants, and its thorns can make removal or management difficult.

Signs to watch for:

• Compound leaves with multiple leaflets

• Sharp thorns on branches and stems

• Clusters of fragrant white flowers in late spring

Managing Woody Invasive Plants

Woody invasive plants are tough to control, but early intervention is key. Your Personal Gardener & Arborist provides professional Invasive Species Control services to protect your landscape, including:

• Identification of invasive woody plants

• Targeted removal and treatment

• Soil and site management to prevent regrowth

• Long-term monitoring to keep your property free of invasive species

Whether you're dealing with dense shrubs or aggressive trees, YPGA creates customized plans to restore and protect your landscape while maintaining its beauty and health.

Concerned about woody invasive plants on your property?

Contact YPGA today to schedule an Invasive Species Control consultation and reclaim your landscape. https://www.ypgausa.com/contact