HERBACEOUS WEEDS 



Ditchbank Weeds 



Where practical, livestock grazing affords the least expensive and most 

 effective way of controlling most ditchbank weeds. In many instances, 

 however, herbicides can be used to advantage. 



(1) For annual and perennial broadleaved weeds where few or no weed 

 grasses are present : Amine or low-volatile ester of 2,4-D at 1 to 2 pounds 

 per acre applied during early growth stage. Repeat as necessary to main- 

 tain control. 



(2) For annual weed grasses where no broadleaved weeds are present : 

 Dalapon at 6 to 10 pounds per acre, amitrol at 4 to 6 pounds per acre, 

 or dinitro-fortified fuel oil at 60 to 80 gallons per acre, when grasses are 

 small. 



(3) For perennial grasses such as Johnsongrass, Bermudagrass, quack- 

 grass, canarygrass, Paragrass, and reed grasses : Repeated applications 

 of dalapon at 20 to 30 pounds, amitrol at 8 to 12 pounds, or aromatic oil 

 or dinitro fuel oil at 120 to 160 gallons per acre. Oil treatments often 

 must be repeated every 3 or 4 weeks to eliminate the weeds in 1 or 2 

 growing seasons. Usually, 1 or 2 applications of amitrol or 2 to 3 appli- 

 cations of dalapon per year will maintain adequate control. 



SOIL STERILIZATION 



The term "soil sterilization" refers to nonselective weed control in 

 which the soil is rendered unproductive for varying durations but not 

 permanently. 



Soil sterilants are used to control all vegetation on an area. Few, if 

 any, chemicals alone will kill all species of plants at rates of application 

 that would be economically feasible. For this reason, herbicide mixtures 

 are finding wider use for soil sterilization. 



Sodium chlorate at 500 to 1,800 pounds per acre, borax at 1,800 to 4,800 

 pounds, sodium arsenite at 300 to 1,200 pounds, the urea herbicides- - 

 monuron and diuron--at 20 to 100 pounds, and mixtures of these herbicides 

 with 2,4,5-T, 2,4-D, dalapon, or TCA and fortifying agents, such as the 

 herbicidal oils, the dinitro compounds, and pentachlorophenol, may be used 

 for control of vegetation on ditchbanks, railroad rights-of-way, industrial 

 sites, and on other noncultivated areas. Use the higher rates of application 

 if semipermanent soil sterilization is required and the lower rates if con- 

 tact kill or temporary soil sterilization is the objective. The treatments 

 suggested above will render most soils unproductive for periods of 30 days 

 to 4 years or more depending on the chemical used, the soil type, and a 

 number of soil properties and climatic factors. 



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