Weed Management Handbook

Poor turf culture is a major reason for weedy lawns. Any effort to control weeds in turf should start with improving cultural practices (mowing, fertilization and irrigation). Properly implemented primary cultural practices will reduce the turfgrass susceptibility to weed encroachment and prevent conditions conducive to weed growth and development.

bentazon (Basagran T&O, Broadloom)

Rate 0.5 lb ai/A (1 pint/A Basagran)

Time Spring to early summer, depending on growth stage of weeds.

isoxaben (Gallery 75DF, SC, 2.5DG and several others)

Perennial groundcovers and bulbs

Rate 0.495 lb ai/A (0.66 lb/A Gallery 75DF)

Time Late winter and early spring. 2 to 4 weeks after planting, before bulbs and annual weeds emerge. Also may apply after bulbs emerge but before they flower.

spunbonded polypropylene + trifluralin (Typar Biobarrier)

bentazon (Basagran T&O)

Rate 0.5 lbs ai/A (1 pt/A Basagran)

Time Spring to early summer, depending on growth stage of weeds.

benefin + oryzalin (XL 2G)

Rate 200 lb/A per application

Time Apply before target weeds germinate.

Remarks Precisely calibrate application equipment, preferably at half rates, to enable two perpendicular passes for increased accuracy. Inhibits cell division or mitosis, primarily in roots. At least 2 months between applications; do not exceed 600 lb/A per year.

dichlobenil (Casoron 4G)

Rate 4 to 6 lb ai/A (100 to 150 lb/A granular product)

Time Apply midwinter immediately before a cold rain to reduce volatility and enhance weed suppression.

clethodim (Envoy and others)

Dahlia, daylily, and iris

Rate 0.1 to 0.25 lb ai/A

Time Apply to actively growing grasses.

benefin + oryzalin (XL 2G)

Bulb iris, tulip, and narcissus

Rate 1.5 to 3 lb ai/A

Time Apply 2 to 4 weeks after planting but before weeds germinate, then incorporate immediately with shallow cultivation (1 to 2 inches) or with overhead water.

EPTC (Eptam 7E)

Dahlia and daylily

Rate 5 lb ai/A

Time Apply preplant and incorporate immediately 2 to 3 inches deep for annual weeds and 6 inches deep to suppress growth of certain perennial weeds.

Remarks Rotate fields to reduce degradation by microorganisms that increase with continual use of EPTC.