Weeds & Invasive Plants

A weed is any plant growing in a location where it is not wanted and is often in competition with desirable cultivated plants. Use the guide below to learn more about common weeds of Wisconsin.

Invasive Weed Identification Videos

The Renz Lab has produced a series of short videos instructing viewers how to correctly identify a variety of terrestrial invasive plant species found in Wisconsin.

General Weeds Resources

Discover a variety of resources on weeds. Dive into guides, articles, and websites below!

Creeping charlie

DNR Invasive and Regulated Plants List
Code NR 40 makes it illegal to possess, transport, transfer or introduce certain invasive species in Wisconsin without a permit.

Invasive Plant Management
A series of factsheets discussing the identification and control of common invasive plant species. Mechanical, cultural, and chemical control methods are discussed in detail.

Wisconsin Terrestrial Invasive Plant Presence (WISTIPP) Viewer
An online interactive map that makes it easy to view and download terrestrial invasive plant reports in Wisconsin.

Weed Management Herbicide Trials
Weed management reports intended to help farmers, restoration ecologists, landowners, and researchers stay up to date on the latest and most effective herbicides for their land management goals.

10 Things to Consider for Weed Management When Establishing Pollinator Plantings
In this video, you will learn about Mark Renz’s research on weed management options and what factors you should consider when planning and establishing pollinator plantings.

Photo left: Creeping Charlie

Discover our most popular weed articles below!


Controlling Creeping Charlie
A difficult to control perennial weed in the mint family that spreads by seeds, rhizomes and creeping stems that root at the nodes.

Common Mullein
An herbaceous biennial or short-lived perennial with a deep tap root.

Common Purslane
A highly variable, weedy plant in the purslane family (Portulacaceae) with a wide distribution.

A common plant native to Eurasia but has naturalized in all parts of the Northern Hemisphere.

Wild Parsnip
An aggressive Eurasian member of the carrot family that grows in sunny areas with sap that can cause phytophotodermatitis.

Photo left: Common Mullein

All Articles

Click on any photo or name below to learn more!

Barnyardgrass – Echinochola crusgalli

Biennial Thistle Comparison

Biennial Wormwood – Artemisia biennis

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Black Medic, Medicago lupulina

Blackseed Plantain – Plantago rugelii

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Bull Thistle – Cirsium vulgare

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Carpetweed, Mollugo verticillata

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Catchweed Bedstraw, Galium aparine

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Chicory, Cichorium intybus

Comfrey – Symphytum officinale

Common and Glossy Buckthorns

Common Burdock – Arctium minus

Common Chickweed – Stellaria media

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Common Groundsel, Senecio vulgaris

Common Lambsquarters – Chenopodium album

Common Mullein – Verbascum thapsus

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Common Mullein, Verbascum thapsus

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Common Purslane, Portulaca oleracea

Common Ragweed – Ambrosia artemisiifolia

Common Weed Seedlings of the North Central States

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Common Yellow Woodsorrel, Oxalis stricta

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Controlling Creeping Charlie, Gleochoma hederaceae

Creeping Charlie

Cucumber Mosaic

Curly Dock – Rumex crispus

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Dame’s Rocket

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Dandelion, Taraxacum officinale

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Dodder, Cuscuta spp.

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Field Pennycress, Thlaspi arvense

Galinsoga – Galinsoga quadriradiata

Garlic Mustard

Giant Foxtail – Setaria faberi

Giant Ragweed – Ambrosia trifida

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Henbit, Lamium amplexicaule

Herbicide Damage

Hoary Alyssum – Berteroa incana

Horseweed (Marestail) – Conyza canadensis

Identifying grasses in Wisconsin

Invasive Exotic Shrub Honeysuckles

Invasive Phragmites

Japanese Knotweed:

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Jewelweed, Impatiens capensis

Milkweed (Ornamental Plants Toxic to Animals)

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Mulches for Home Gardens and Plantings

Musk Thistle – Carduus nutans

Palmer Amaranth – Amaranthus palmeri

Plumeless Thistle – Carduus acanthoides

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Poison Ivy

Purple Loosestrife

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Queen Anne's Lace, Daucus carota

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Spotted Spurge, Chamaesyce (=Euphorbia) maculata

Tall / Common Waterhemp

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Velvetleaf, Abutilon theophrasti

Wild Buckwheat – Polygonum convolvulus

Wild cucumber invading area with Vijai Pandian (August 26, 2019)

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Wild Cucumber, Echinocystis lobata

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Wild Parsnip

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Yellow Goatsbeard, Tragopogon spp.

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Yellow toadflax, Linaria vulgaris

For more weeds and invasive plant information, see the resources at the Renz Weed Science Lab.

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