Weed Management Handbook

2,4-D or picloram (Tordon) or dicamba (Clarity) or 2,4-D + dicamba (Weedmaster) or triclopyr + 2,4-D (Crossbow)

Rate 1 to 2 lb ae/A 2,4-D LV ester or 2,4-D amine; or 0.25 lb ae/A picloram; or 1 lb ae/A dicamba; or 2 quarts/A Weedmaster; or 1.5 to 2 quarts/A Crossbow

2,4-D ester

Rate 2 lb ae/A

Time Apply after all plants have emerged but before flowering.

Remarks Foliage must be thoroughly wet. Use 50 gal/A of water.

Caution Avoid drift to sensitive crops.

Site of action Group 4: synthetic auxin

2,4-D LV ester

Rate 3 lb ae/A

Time Apply when rabbitbrush has 3 inches of new spring growth.

Remarks Soil moisture should be above wilting coefficient. If Sandberg bluegrass has dried up or lost its color, soil is too dry for rabbitbrush active growth, and it is too late to spray.

bromacil + diuron (Krovar I DF)

Rate 9.6 lb ai/A (12 lb/A)

Time Apply before weeds emerge.

Remarks Rain is needed to activate this herbicide.

Caution Nonselective weed control. Do not apply to areas where desirable plant roots extend.

2,4-D amine or 2,4-D LV ester

Rate 1 to 2 lb ae in 10 to 20 gal water for spot treatments.

Time Apply every 3 weeks during growing season or when new seedlings appear.

Remarks Seed will germinate throughout the summer when moisture is available.

Caution Avoid drift to sensitive crops.

fenoxaprop (Acclaim or Horizon)

Rate 0.15 to 0.25 lb ai/A

Time Apply to actively growing plants with at least two leaves. Larger plants are harder to control.

Remarks Refer to product label for crops and sites on which fenoxaprop may be used.

Caution Do not use a crop oil or surfactant.

picloram (Tordon)

Rate 0.25 to 0.5 lb ae/A

Time Apply in May to July. Timing is not critical.

aminocyclopyrachlor + metsulfuron methyl (Streamline)

Rate 1.9 to 3.8 oz/A aminocyclopyrachlor + 0.6 to 1.2 oz/A metsulfuron (4.75 to 9.5 oz/A of product)

Time Apply to actively growing woody plants.

2,4-D amine

Rate 4 lb ae/A

Time Apply at the bud stage of growth.

Remarks Repeat treatments if needed. Good grass cover helps control perennial pepperweed.

Caution Avoid drift to sensitive crops.

Site of action Group 4: synthetic auxin

simazine (Princep)

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

Site of action Group 5: photosystem II inhibitor

Chemical family Triazine