HPIPM:Blue mustard

Taxonomy

Domain	Eukarya
Kingdom	Plantae
Phylum	Magnoliophyta
Class	Magnoliopsida
Superorder	Rosanae
Order	Brassicales
Family	Brassicaceae
Genus	Chorispora

Scientific Name

Chorispora tenella

Common Name

blue mustard

Blue mustard(Chorispora tenella)

Author: Drew Lyon, University of Nebraska Lincoln

Identification and Life Cycle

Blue mustard (Chorispora tenella) is an introduced annual weed in the mustard family (Brassicaceae). Flowers are bluish-purple to purple with four petals. Plants can reach 6 to 18 inches in height. Stems and leaves are sparsely to moderately covered with small, gland-tipped hairs. Seedlings have oval and somewhat glandular leaves. Leaves are lance-shaped with wavy or coarsely-toothed margins. Fruits (siliques) are long and slender and about 1 to 1 1/2 inches long. Seeds are smooth, round, about 1/16 of an inch in diameter, and red to brown in color. It has a stout taproot.

Habitats

Blue mustard occurs in dry disturbed sites such as waste places, pastures, and along roadsides and railroad right-of-ways. It is also a problem in winter annual crops such as winter wheat and perennial crops like alfalfa.

Impacts

Blue mustard can reduce crop yields. Dairy cattle grazing in infested pastures may produce off-flavor milk.

Biology and Ecology

Seeds germinate in late summer and fall, and the plant overwinters as a rosette. Bolting occurs in March. Blue mustard flowers in early April. Viable seeds can be produced 10 days after bloom. Plants reproduce only from seed.

Biological Control

There are no biological control agents available for blue mustard

Mechanical and Cultural Control

Changing crop rotation is suggested for heavily infested fields. Including a spring seeded crop such as corn, sorghum, soybean, oat, proso millet, or sunflower in the rotation to allow two years between winter wheat crops breaks the life cycle of blue mustard. This will reduce the blue mustard population in future winter wheat crops by depleting the soil seed bank. Tilling before plants produce flowers will reduce the amount of seed entering the soil seed bank.

Chemical Control

Consult herbicide labels for additional rate, application, and safety information. Additional herbicide information can be found at http://www.greenbook.net.

Due to constantly changing labels, laws and regulations, the sponsors of this web site assume no liability for the suggested use of any chemicals noted in the management section. Contact your local pest management personnel for current information on labeled pesticides that can be used for the intended plant disease, insect pest or weed.

References

For more information and images please visit IPM bugwood. http://www.ipmimages.org/search/action.cfm?q=blue%20mustard

For more information on blue mustard please see University of Nebraska-Lincoln Extension, Institute of Agriculture and Natural Resources publication G1272: Blue Mustard Control. http://www.ianrpubs.unl.edu/epublic/live/g1272/build/g1272.pdf