Effect of Spray Mixtures Containing 2,4-Dichlorophenoxyacetic Acid, Urea, and Fermate on the Growth of Grass

Abstract

Herbicidal dosages of 2,4-D were applied in the spring to Kentucky bluegrass, red top and red fescue grasses growing in mixed stand to eradicate weeds. The acid was found to have a mild retarding effect on the rate of growth of the grasses. Addition of urea to the spray mixtures counteracted the retarding effects on grass growth of 2,4-D without interferring with its selective weed-killing properties. A spray soln. composed of 3% urea and 0.15% of the ammonium salt of 2,4-D, when applied at the rate of 5 gallons per 1000 sq. ft., eradicated narrow leafed plantain (Plantago lanceolata) and induced a greening of the grass within 10-14 days after spraying. A fungicide, Fermate, when incorporated in the above spray mixture at the rate of 2 lbs. per 100 gal., had no effect on the herbicidal properties of the spray. The fungicidal value of Fermate in such mixtures was not evaluated.