Title

A Guide to North Dakota Noxious and Troublesome Weeds

(W1691, Revised April 2020)
Summary

This publication includes photos of all North Dakota state and county listed noxious weeds as well as "troublesome" plants such as poison ivy. Methods to identify and control each weed are discussed and why the plant is a concern in the state is explained. This is a pocket sized version of the publications W1411, Identification and Control of Invasive and Troublesome Weeds in North Dakota.

Lead Author
Lead Author:
Revised by Joe Ikley Extension Weed Specialist and Assistant Professor Department of Plant Sciences
Availability
Availability:
Available in print
Publication Sections

This guide was made with collaboration of the author with North Dakota State University Extension and the North Dakota Department of Agriculture, with funding from the U.S. Forest Service. This publication is designed to help land managers identify the state- or county-listed noxious weeds. Other species included are those with the most potential to spread within the state or into North Dakota from bordering states.

The following symbols are used to designate legally listed noxious weeds:

State Listed Icon
State Listed
County Listed Icon
County Listed
Early detection – rapid response
Early detection – rapid response

The following symbols are used to designate control methods available for each species:

Biological (insects)
Biological (insects)
Chemical (herbicides)
Chemical (herbicides)
Grazing
Grazing
Removal by hand
Removal by hand
Removal by digging
Removal by digging

Control recommendations are current at publication, but options change rapidly. Before beginning any management program please consult with your local county Extension agent and/or weed officer for the latest chemical, cultural and biological control recommendations.

These symbols warn of plants that may be toxic to livestock or humans:

Do not allow livestock to graze
Do not allow livestock to graze
Poisonous plants
Poisonous plants
Do not touch with bare skin
Do not touch with bare skin

The plant species identified in this guide are considered noxious and/or pose a threat to North Dakota and the Midwest. North Dakota law requires state-listed noxious weeds to be controlled. Other weeds have been designated as noxious weeds in one or more counties throughout the state. These weeds are required to be controlled within their listed counties. For ease of identification, state- and county-listed noxious weeds have been designated with icons throughout the guide.

Chemical control recommendations are updated annually in the “North Dakota Weed Control Guide,” Extension publication W253, available from county offices or on the Web at www.ndsu.edu/weeds

For the latest in biological control options, contact the North Dakota Department of Agriculture and/or the local staff of the U.S. Department of Agriculture – Animal and Plant Health Inspection Service in Bismarck.

Absinth wormwood

Absinth Wormwood
Absinth Wormwood
Absinth Wormwood

Absinth wormwood

(Artemisia absinthium L.)

Absinth wormwood is a perennial plant that is easily recognized by the strong sage fragrance. Absinth wormwood emerges in early spring and grows to a height of 3 to 5 feet. The leaves are light green and divided two or three times into deeply lobed leaflets. Flower stalks grow from upper leaf nodes and produce many small yellow flower heads from late July to mid-August. Each fruit contains one seed, which is scattered easily by wind, animals and in hay.

Absinth wormwood is a member of the sagebrush family, but dies back in the fall and regrows from the soil surface each spring. The plant is found on dry soils, overgrazed pastures, gravelly areas and roadsides.

Absinth wormwood reduces forage production, gives milk of cattle that graze it a sage taste, and produces a fine pollen that causes allergies and can induce asthma. The oil from flowers is used to prepare vermouth and absinthe and is an ingredient in liniments.

State Listed Icon
State Listed
Chemical (herbicides)
Chemical (herbicides)

Baby’s breath

Baby's Breath
Baby's Breath
Baby's breath leaves
Baby's Breath

Baby’s breath

(Gypsophila paniculata L.)

Baby’s breath is a perennial plant that regrows from a large taproot. The plant can grow to 3 feet tall, is very branched, and is easily identified by the numerous small white flowers. The leaves are opposite, narrow and pubescent. The plant will grow in a variety of conditions and the taproot can exceed 10 feet deep. The tiny black seeds are spread in the fall when branches break off and are blown by the wind tumbleweed fashion. Each plant can produce more than 10,000 seeds.

Baby’s breath commonly is used as a filler in bouquets and is spread easily by seed when the flowers are discarded. The plant will form a dense stand and displace desirable grasses and forbs. Baby’s breath was introduced from Eurasia and is a member of the Carnation or Pinks family. This plant is a designated noxious weed in neighboring Montana and other western states.

County Listed Icon
County Listed
Chemical (herbicides)
Chemical (herbicides)

Black henbane

Black henbane
Black Henbane
Black Henbane
Black Henbane

Black henbane

(Hyoscyamus niger L.)

Black henbane is a member of the nightshade family and is a non-native annual weed in North Dakota. Black henbane grows up to 5 feet tall. The plant has coarse, pubescent and often sticky leaves and branches. The leaves are large (6 by 8 inches), alternate, coarsely toothed, lobed and grayish green. Flowers are funnel-shaped, five-lobed, brownish yellow with dark purple veins. The seeds are contained in pineapple-shaped capsules and are gray brown to black. Black henbane can produce thousands of seeds per plant.

Seeds germinate and produce a rosette with a large whitish branched taproot the first growing season. The plant bolts and flowers from June until the first frost the second season. The plant has an unpleasant odor throughout its life-cycle. Black henbane contains alkaloids that can poison animals but is unpalatable and rarely eaten. All parts of the plant are toxic to humans. Even just smelling the flowers can cause headaches and nausea.

County Listed Icon
County Listed
Chemical (herbicides)
Chemical (herbicides)
Do not allow livestock to graze
Do not allow livestock to graze
Poisonous plants
Poisonous plants

 

False chamomile aka German chamomile

False chamomile aka German chamomile
False chamomile aka German chamomile
False Chamomile
False Chamomile

False chamomile aka German chamomile

(Matricaria recutita L.)

False chamomile resembles the common daisy. The plant is an annual with white flowers and blooms from May through August. False chamomile will grow from 6 to 18 inches tall and has very finely divided leaves from 0.75 to 2.5 inches long. The dark brown seeds are 2 millimeters long, with three ribs on one side and a broad brown central area on the other. False chamomile has a pleasant aroma, which distinguishes this species from the close relative scentless chamomile.

Spring- and fall-emerging plants can reduce wheat yield but are easily controlled with sulfonylurea herbicides. False chamomile has been used for medicinal purposes for hundreds of years. The plant is used to make chamomile tea which is reported to have relaxation benefits. Pollen from this plant will cause allergic reactions similar to ragweed.

County Listed Icon
County Listed
Chemical (herbicides)
Chemical (herbicides)

Common burdock

Common burdock
Common burdock
Common burdock
Common burdock

Common burdock

[Arctium minus (Hill) Bernh.]

Common burdock is a taprooted biennial that only reproduces by seed. The first year plant forms large heart-shaped leaves which look similar to rhubarb. The plant bolts in the second season and can grow 3 to more than 6 feet tall. The leaves are dark green above and whitish green and wooly-hairy below with toothed margins. Flowers are pink, purple or white and about 0.75 inch across. Flower heads are enclosed in a prickly bur that has numerous wooly bracts, tipped with hooked spines.

Common burdock is native to Europe but now is found throughout North America. The plant is often found in partially shaded wet areas, along roadsides and ditch banks. The plant spreads by seeds that are found within the burs that cling to hair, fur and clothing. The plant is an alternate host to powdery mildew and root-rot that can spread to commercial crops. The burs can cause eye disease, mouth sores and skin infections of animals.

County Listed Icon
County Listed
Biological (insects)
Biological (insects)
Chemical (herbicides)
Chemical (herbicides)
Removal by hand
Removal by hand
Removal by digging
Removal by digging

Common milkweed

Common milkweed
Common milkweed
Common milkweed flower
Common milkweed flower
Common milkweed pod
Monarch butterfly larvae
Monarch butterfly larvae

Common milkweed

(Asclepias syriaca L.)

Common milkweed is a robust plant native to North America and is best known as a primary food source for the monarch butterfly. The plant is a perennial that grows 3 to 5 feet tall and reproduces by underground rootstocks and seeds. The stem is erect and fleshy with large opposite leaves 3 to 5 inches wide and 6 to 10 inches long. A thick, white, milky latex is found throughout the plant. Flowers are arranged in tight clusters at the top of the plant and are pink to white. Common milkweed has shallow fibrous roots. Milkweed grows in a wide range of soil moisture conditions, but can become dense under medium or high moisture levels.

Seed pods are 3 to 5 inches long and contain dozens of flat reddish-brown seeds with tufts of hairs that allow the seed to travel in the wind. Milkweed has been used for medicinal, industrial, decorative purposes and even for food, despite having some degree of toxicity. Common milkweed is extremely difficult to control.

County Listed Icon
County Listed
Biological (insects)
Biological (insects)
Chemical (herbicides)
Chemical (herbicides)

Common mullein

Common Mullein