Weed Management Handbook

2,4-D or MCPA

Rate 1.5 lb ae/A

Time Apply in seedling to rosette stage of growth.

Remarks Most effective soon after plants emerge. Adding a wetting agent may enhance control.

Caution Do not graze treated area until plants have dried up after spraying.

2,4-D (various products)

Rate 1.43 to 1.9 lb ae/A

Time Apply to growing hawkweed before buds form.

Remarks These species may need re-treating and/or the higher rate even under ideal conditions.

Caution Product injures or kills sensitive broadleaf forages. Do not contaminate water.

2,4-D (various products) or MCPA (various products) or clopyralid (Transline)

Remarks Reported to control this plant, although data are lacking in the Pacific Northwest. Follow label instructions.

Site of action (all) Group 4: synthetic auxin

Chemical family (2,4-D and MCPA) phenoxy acetic acid; (clopyralid) pyridine

2,4-D LV ester

Rate 1 to 2 lb ae/A

Time Apply in early spring when plants are actively growing before bloom stage.

Remarks Halogeton is poisonous to livestock. Chemical control is effective but will be futile unless desirable plants occupy the site immediately.

2,4-D LV ester

Rate 2 lb ae/A

Time Apply in early spring when new growth and seedlings are fully emerged.

Remarks After plants reach the bloom stage, control decreases.

Caution Avoid drift to sensitive crops.

Site of action Group 4: synthetic auxin

Control gorse in two stages. First, control established plants. Second, control new plants emerging from seeds that may have been resting in the soil for as long as 30 years. The most effective control program usually combines herbicides, burning, and cultivation or mowing. Establishing competitive pasture species, forest trees, or other crops helps resist gorse invasion as well as other weeds. A publication on the biology and control of gorse (Gorse, PNW 379, revised July 2001) is available from the Extension Service.

glyphosate

Rate 0.38 to 0.75 lb ae/A

Time Apply to actively growing plants emerged before boot stage.

Remarks Use along field edges and other non-cropped areas to prevent spread into bordering fields. Can be used as a spot treatment in certain crops (refer to label).

Caution Glyphosate is not selective.

2,4-D LV ester

Rate 1 to 2 lb ae/A

Time Early spring, preferably mid-April, before garlic is more than 8 inches tall. Re-spray annually to achieve effective control.

Seedlings of this soft, hairy annual are upright, but as plants mature they develop prostrate stems. Leaves on stems resemble those of bindweed, but fluvellin is in the snapdragon family. It has pale yellow flowers with a narrow spur and a purple upper lip. This weed is spreading into cropland throughout the Willamette Valley of Oregon and is of particular concern in spring-planted tall fescue grown for seed among other grass grown for seed species.

2,4-D (various products)

Remarks Reported to control this plant, although data are lacking in the Pacific Northwest. Follow label instructions.

Site of action Group 4: synthetic auxin

Chemical family Phenoxy acetic acid