Weed Management Handbook

clethodim (Select Max, Select Max, Clethodim 2E, Tide USA Clethodim 2EC, Willowood Clethodim 2EC, Shadow, Shadow 3EC, Cleanse)

Burndown of volunteer Round up Ready corn before re-planting corn

Rate 0.047 lb ai/A or 0.0455 lb ai/A (3 fl oz/A for Clethodim 2E or 6 fl oz/A for Select Max)

Time Up to 6 days before planting corn.

bentazon (Basagran, Bentazon 4)

Rate 0.75 to 1 lb ai/A

Time Apply when yellow nutsedge is 6 to 8 inches tall and, if needed, again at the same rate 7 to 10 days later.

glyphosate (several trade names)

Rate 0.75 to 3.75 lb ae/A

Time Apply to actively growing weeds before silking of corn.

Remarks Rates depend on weed species and growth stage as specified on label.

clopyralid (Stinger)

See "Corn-Postemergence" in this section of this handbook.

Rate Apply 0.124 to 0.25 lb ae/A (0.33 to 0.66 pint/A of Stinger)

Time Any time after sweet corn emerges until it is no more than 18 inches tall.

paraquat (Gramoxone SL3.0, Parazone 3SL)

Rate 0.5 lb cation/A (1 to 2 pints/A)

Time Apply when corn is at least 10 inches tall with nozzles arranged to spray no higher than the lower 3 inches of corn stalks.

Remarks Apply by ground in at least 20 gal/A water, and add a nonionic surfactant or crop oil concentrate.

2,4-D (several trade names)

Rate 0.5 to 1.0 lb ae/A. Consult label, as 2,4-D labels vary in rates.

Time Apply when corn is actively growing.

Remarks Applying without drop nozzles to corn over 8 inches tall may increase lodging and interfere with normal tassel emergence. Use drop nozzles to avoid applying to corn leaves.

acetochlor (Surpass, Cadence, Surpass NXT, Harness)

For use on field corn, production seed corn, Silage corn, sweet corn, and popcorn.

Rate 0.8 to 3 lb ai/A. Consult appropriate label for rates.

Time Apply preplant or preemergence.

Herbicide-resistant field corn is now commonly grown in the Pacific Northwest. There are four major types of herbicide resistant corn: including some that are genetically engineered; and some that are developed by genetic selection of tolerant corn individuals and/or varieties. Failure to apply the correct herbicide to the correct crop will result in serious injury to the corn. Refer to the appropriate herbicide label for guidelines on how to use each product on herbicide-resistant corn.

carfentrazone (Aim and other trade names)

Rate 0.031 to 0.096 lb ai/A (2.0 to 6.1 oz/A Aim EC)

Time Harvest aid, when 75% of bolls have turned brown, up to day of harvest.

Remarks Apply with MSO or COC at 1 to 2 % v/v, in a minimum of 15 GPA. The addition of AMS may improve efficacy.

bromoxynil (Broclean, Maestro, and other trade names)

Rate 0.25 lb ai/A (1 pt/A Broclean)

Time Apply when flax is 2 to 8 inches tall. Do not apply during or after bud stage, or within 75 days of harvest.

Remarks Do not apply with crop oil concentrate, surfactants, or nitrogen solutions.