Introduced Plants Managed at Nachusa Grasslands

Introduced plants have been intentionally or accidentally brought by humans into areas outside of their natural habitats. These plants can spread rapidly, displacing or destroying native species.

The Nachusa Grasslands staff and stewards manage about 30 different introduced plants. Based on their area responsibilities, they often prioritize controlling certain species over others. The following are a few of the plants that our staff and stewards deal with throughout the year.

---

Amur honeysuckle

• Scientific Name: Lonicera maackii
• Origin: Asia
• Ecological Threat: Amur honeysuckle infests many savannas and woodlands and is difficult to eradicate. Its large thickets prevent native shrubs and plants from thriving. Birds eat the berries and distribute them widely, where they easily germinate.
• Management Methods: Applying herbicide to each shrub’s basal bark or cut stems. Fire top kills honeysuckle but does not kill the root.
• Lessons Learned by Bill Kleiman — December 2016

 
Autumn and wild olive

• Scientific Names: Autumn olive (Elaeagnus umbellata); wild olive (Elaeagnus angustifolia)
• Origin: Japan
• Ecological Threat: Autumn olive can form dense, shady, shrub clusters, closing open areas and suppressing the growth of native plants that require sunny conditions to survive.
• Management Methods: Applying herbicide to each shrub’s basal bark or cut stems. Fire top kills autumn olive but does not kill the root.  

Birdsfoot trefoil

• Scientific Name: Lotus corniculatus
• Origin: Europe, Asia, and North Africa
• Ecological Threat: Dense colonies can exclude native species. Plants produce abundant seeds which stay in the soil bank for years.
• Management Methods: Spot or boom spraying herbicide; clipping and disposing of seed heads.

• USFS Handout​
• Managing BFT by Hank and Becky Hartman​​

Common buckthorn

• Scientific Name: Rhamnus cathartica
• Origin: Europe
• Ecological Threat: Shrubs can form thickets that out-compete native plants for nutrients, light, and moisture.
• Management Methods: Applying herbicide to each shrub’s basal bark or cut stems.

Leafy Spurge

• Scientific Name: Euphorbia virgata
• Origin: Europe and Asia
• Ecological Threat: Latex sap is an irritant and is toxic to some animals. Dense colonies can exclude native wildlife.  
• Management Methods: Apply herbicide when in flower (summer) and repeat in the fall.
• Leafy Spurge; A Weed to Watch For by Bill Kleiman — May 2017

Multiflora rose

• Scientific Name: Rosa multiflora​
• Origin: Asia
• Ecological Threat: Thorny, bushy shrubs smother native vegetation.
• Management Methods: Applying herbicide to each shrub’s basal bark or cut stems.

Queen Anne's lace

• Scientific Name: Daucus carota
• Origin: Europe and Southwest Asia
• Ecological Threat: Each Queen Anne’s lace plant produces thousands of seeds, so they can spread quickly, especially in disturbed areas, crowding out native species.
• Management Methods: Digging, using special spades to cut the root underground; clipping and disposing of seed heads.

Red clover

• Scientific Name: Trifolium pratense
• Origin: Europe, Western Asia, and Northwest Africa
• Ecological Threat: Red clover may spread and displace desirable vegetation if not properly managed.
• Management Methods: Spading, spot spraying, or applying herbicide to cut stems; clipping and disposing of seed heads.

Reed canary grass

• Scientific Name: Phalaris arundinacea
• Origin: Europe and Asia
• Ecological Threat: Reed canary grass forms large monocultures and crowds out native species, building up a tremendous seed bank that germinates year after year.
• Management Methods: Applying herbicide; clipping and disposing of seed heads.

Wild parsnip

• Scientific Name: Sativa pastinaca
• Origin: Europe and Asia
• Ecological Threat: Infestations can spread and form dense stands, crowding out native vegetation.
• Management Methods: Applying herbicide before plants bolts; spading and hauling out flowering plants, being careful to avoid sap on skin, which can cause blisters

Yellow and white sweet clover

• Scientific Names: Yellow (Melilotus officinalis); White (Melilotus alba)
• Origin: Europe
• Ecological Threat: Sweet clovers degrade open grasslands by crowding and shading native plants, thereby reducing species diversity.
• Management Methods: Spading, mowing, spraying patches, or applying herbicide to cut stems; clipping and disposing of seed heads.

---

For more information on introduced flora at Nachusa Grasslands, see Herbicide Use, and Introduced Woody Identification web pages.

---

UPDATED 02/2026