The issue: Oxeye daisy

Oxeye daisy (Leucanthemum vulgare) is a creeping, spreading perennial that was originally brought to the U.S. from Europe as an ornamental. It can grow up to 3 feet tall. It’s often found in grasslands, meadows, pastures, and disturbed places. Oxeye daisy is listed as a noxious weed in Idaho.

The white-with-yellow-center flowers, which are borne at the ends of the stems (single or branched), are smaller than Shasta daisies. Basal leaves are spoon-shaped with coarse teeth. Leaves on the flower stem get progressively smaller and are sessile (no petiole).

The extensive rhizome system of Oxeye daisy leads to dense patches that choke out native plants. Seeds may be included in wildflower packets.

Oxeye daisy reproduces by seeds and rhizomes. Seeds may remain viable for up to 39 years in field conditions. The seeds are dispersed through water, animals, muddy boots, vehicle tires and clothing.

Integrated pest management options:

· Prevention: Don’t plant wildflower mixes that contain oxeye daisy, or that don’t identify the contents; keep ditch banks free of seed-producing weeds; identify and control new weed infestations; feed livestock clean hay for several days in a corral between fields.

· Mechanical: Hand-pull small patches, removing as much root as possible; frequent tillage can reduce rhizome regrowth. Kill the root and eliminate seed production.

· Cultural: Don’t overgraze pastures; manage land to provide good competition from desirable plants

· Biological: None.

· Chemical: Apply in fall to rosettes or spring to actively growing plants before bud stage — aminopyralid, chlorsulfuron, clopyralid, dicamba, glyphosate, imazapyr, metsulfuron, picloram (restricted use). Be sure the weed and landscape or crop situation are listed on the label. Always read and follow herbicide label directions.

Combine them:

Combine different IPM options over a period of years to help improve the effectiveness of your efforts.

For more information, contact Ron Patterson, University of Idaho Extension horticulture/agriculture educator in Bonneville County, at 208-529-1390 or rpatterson@uidaho.edu.