2012-08-30_REPORT - M1978135HR - Laserfiche WebLink

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Accurate Calibration Saves Money, the Environment and Improires Weed Control You may have seen what over or under application of herbicides can do. Too little herbicide applied per acre can mean poor weed control. On the other hand, too much herbicide can cause injury to usually non - susceptible desirable plants. Over application of anything. including rock salt for snow melt, discarded petroleum products, and even weeds or grass clippings can be a soil sterilant if applied in excess. A few minutes spent on calibration can save lots of money in wasted herbicides, protect the environment from high soil concentrations of pesticides and will give you satisfactory results which can be duplicated. Backpack Sprayer Calibration 1. Mark off an area 18.5 ft. by 18.5 ft (NOTE: The area you mark off does not have to be 18.5' x 18.5'. It may be any length and width combination that equals 342.25 square feet). Since this is 1/128 of an acre and there are 128 oz in a gallon, no math will need to be done. 2. Fill your sprayer with water. 3. Time yourself while spraying the area you have marked off. Record the time it took you to spray the marked area in seconds. 4. Spray into a container for the amount of time you recorded in step #3. 5. Measure the water you collected in step #4 in ounces. The number of ounces you have collected is equal to the number of gallons you are applying per acre. Ounces collected = GPA. Time applications in seconds (step 3) Measure water collected in oz. = GPA (step 5) How much pesticide do I put in each backpack? a. Divide the capacity of your backpack in gallons by the GPA from step #5. Record this number. b. From the pesticide label, determine the amount of pesticide you want to apply per acre in ounces. c. Multiply the pesticide rate per acre in ounces by the result obtained in (b) above. The answer you will get is the amount of pesticide to add to each backpack in ounces. 1. Capacity of backpack in gallons GPA (step 5) _ 2. Application rate in oz. (b) X (a) = (c) (a) EXAMPLE: You have marked off an area equal to 342.25 sq. ft. You spray the area and it takes you 35 seconds. You collect the output from your sprayer for 35 seconds. -- i You measure the water you have collected for 35 seconds and find you have collected 62.5 ounces. You are applying 62.5 gallons per acre. You want to apply 1 pint (16 oz.) of Tordon 22K per acre. Your back pack will hold 4.5 gallons. You divide the 4.5 gallons your backpack holds by the 62.5 gallons per acre you are applying per acre and get .0725 (NOTE: the number you get in this operation is the percent of one acre you can do with one backpack). You multiply the 16 oz. of Tordon 22K by .0725 which equals 1.12 ounces of Tordon 22K to add to each backpack. Some critical factors about calibration are: • Handgun calibration is individual —each person is different • Water volume output is specific to the speed the applicator travels — faster = less GPA; slower = more GPA. • Uniform ground coverage of spray is critical to accuracy. • Develop a working pace which is comfortable and can be kept up for many hours.