VIII. WEED CONTROL IN LAWNS AND OTHER TURF AREAS 



WEED CONTROL IN LAWN AND TURF SEEDBEDS PRIOR TO ESTABLISHMENT 



When establishing a lawn or seeding turf areas, annual grasses and broadleaved weeds 

 may be controlled by a preplanting treatment of calcium cyanamide. The chemical 

 should be applied and disked or raked to mix it into the upper 1/2- to 1-inch layer of 

 soil at the rate of 50 to 80 pounds per 1,000 square feet. Most effective results are 

 usually obtained by making a split application. Apply 25 to 40 pounds per 1,000 square 

 feet and rake it into the upper 1/2 to 1 inch of soil. Then apply 25 to 40 pounds per 

 1,000 square feet on the soil surface. Seeding of the turf grasses must be delayed for 

 2 to 4 weeks until the toxic effects of the calciunn cyanamide have disappeared. Once 

 the toxic effects have disappeared, the decomposition products of calcium cyanamide 

 serve as an excellent source of nitrogen and calcium, 



WEED CONTROL IN ESTABLISHED LAWNS AND TURF 



Spring Treatments for Control of Crabgrass and Broadleaved Weeds 



( 1 ) Home Lawns. --For the control of crabgrass and broadleaved weeds such as 

 dandelions, plantain, curled dock, wild onion, chickweed, and henbit in home lawns, 

 use a mixture consisting of 2 ounces or 4 tablespoons of PMA (based on any product 

 containing 10 percent PMA by weight) and 1 ounce or 2 tablespoons of an amine salt of 

 2,4-D (any product containing 4 pounds of 2,4-D per gallon of concentrate) in 2 gallons 

 of water per 1,000 square feet. The PMA-2,4-D mixture should be applied just at 

 crabgrass emergence and any time after emergence up to the two-leaf stage of crab- 

 grass growth. Omit the 2,4-D from the mixture and repeat the PMA treatment at 7- to 

 10-day intervals until three applications have been made. 



Potassium cyanate (KOCN) at 3 1/2 ounces or 7 tablespoons in 2 gallons of water per 

 1,000 square feet nnay be used to replace PMA in the treatments described above. MCPA 

 at the same rate of application suggested for 2,4-D may be used instead of 2,4-D in 

 mixtures with PMA or KOCN. 



Chickweed not treated in the fall should be sprayed as soon as it appears in early 

 spring. Use 4 ounces or 8 tablespoons of ammonium DNBP (4,6-dinitro ortho secondary 

 butyl phenol) or 2 ounces or 4 tablespoons of amine DNBP in 1 gallon of water per 

 1,000 square feet of lawn. 



(2) Extensive Turf Areas , --For the control of crabgrass and broadleaved weeds on 

 extensive turf areas a mixture consisting of 1 pound of an amine salt of 2,4-D (or 1 

 quart of an amine salt of 2,4-D from any commercial product containing 4 pounds of 

 2,4-D per gallon of concentrate) and 3/4 pound of PMA (or 6 pints of any PMA formula- 

 tion containing 10 percent PMA by weight) in 40 gallons of water per acre should be 

 applied immediately after crabgrass emergence and any time up to the two-leaf stage 

 of crabgrass growth. Omit the 2,4-D from the mixture and apply two additional treat- 

 ments of PMA alone at 3/4 pound in 40 gallons of water per acre at 7- to 10 -day 

 intervals in order to obtain satisfactory control of crabgrass. 



The first treatment with the PMA-2,4-D mixture will effectively control such broad- 

 leaved weeds as dandelions, plantain, curled dock, wild onion, chickweed, and others. 

 The two additional treatments of PMA alone are required to control crabgrass and 

 other annual grasses. The PMA-2,4-D mixture should be applied immediately following 

 mixing. 



Potassium cyanate (KOCN) at 8 to 16 po\mds in 40 gallons of water used in the same 

 manner as described for PMA above may be used instead of PMA depending on cost 



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