(2) AMS may be applied as crystals to surface of freshly cut stumps at 

 the rate of 1 tablespoon for each 2 inches of stunnp diameter, or the entire 

 stump may be sprayed with a solution containing 4 to 6 pounds of the herbi- 

 cide per gallon of water. 



HERBACEOUS WEEDS 



Ditchbank Weeds 



In many situations careful livestock grazing management affords inexpen- 

 sive and effective control of ditchbank weeds. Factors that influence the 

 kind of management needed to maintain desirable vegetation and prevent 

 erosion on ditchbanks are (a) size and kind of ditchbank, (b) slope length and 

 steepness of the ditchbank, (c) w^hether it is a "dry-run" or "continuous - 

 flow" type of ditch, (d) size of drainage area, and (e) kind of vegetation 

 used to stabilize the banks. In other situations, herbicides maybe used to 

 better advantage. 



( 1 ) For annual and perennial broadleaved weeds w^here few or no weed 

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

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

 control. Some species that do not respond to 2,4-D may respond to 2,4, 5 -T 

 and silvex at the same rate of treatment. 



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

 Dalapon at 6 to 10 pounds per acre, amitrole 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, amitrole 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 w^eeks to eliminate the weeds in 1 or 2 growing 

 seasons. Usually, 1 or 2 applications of amitrole or 2 to 3 applications of 

 dalapon per year w^ill 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 

 w^ould 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, monuron, diuron, and 

 simazine at 10 to 80 pounds, erbon at 80 to 160 pounds, and mixtures of these 

 herbicides with 2,4,5-T, 2,4-D, silvex, dalapon, or TCA and fortifying 

 agents, such as the herbicidal oils, the dinitro compounds, and penta- 

 chlorophenol, may be used for control of vegetation on ditchbanks, railroad 



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