Chapter 24 Flashcards
Calibration
the measurement of the delivery rate of your application equipment. such as the amount of spray mix or granules applied per given unit of area
purpose of calibration
to apply the correct amount of material uniformly so as to achieve the desired pest control without added risks
Why is calibration important and who consequences are there if you fail to calibrate properly?
applying too much pesticide:
violation of label directions
damage to the treated surface, plant, or animal
could lead to illegal residues
increase risks to human health and the environment
wastes money
applying too little:
violation of label directions
result in poor pest control
will cost you more money and time
Identify label information you will need to calibrate a sprayer or granular applicator?
the desired spray rate for liquids or application rate for granules. The label may also tell you how coarse the spray must be, pressure ranges, nozzle types
What should you do to prepare for equipment calibration?
get necessary equipment: stop watch, optical range finder or tape measure, graduated container to collect spray of granules, scale, paper and pencil, calculator
Work clothes and PPE
what are the three things you can change to adjust spray rate?
sprayer pressure
sprayer speed
size of nozzle openings
How does changing sprayer speed affect spray rate
increasing in speed creates a proportional decrease in spray rate
new spray rate = old spray rate * new time / old time
how does changing sprayer pressure affect spray rate
increasing sprayer pressure will increase the amount of spray coming out the nozzle. The increase in flow rate in not proportional to the increase in pressure., You have to increase pressure four fold to double nozzle spray rate
how does changing nozzle openings affect spray rate
the nozzle flow rate with increase if you increase the size of the opening.
Which method is the best choice for making large changes in spray rate
nozzle opening
What factors affect the flow rate of granules and how?
ground speed - flow of granules is not proportional to speed
field terrain will impact the flow of granules
relative humidity can cause clumping and decrease the flow rate
Why do you need to recalibrate a granular applicator each time you switch products
need to use pesticide because flow rate depends on size, shape, and density of granules
How do you calibrate a hand sprayer
to calibrate a hand sprayer measure and mark off an area of 1000 sq ft. practice sprayer the area with water.
Sprayer twice walking and swinging the nozzle back and forth with the second application made at a right angle to the first
time how long it takes you to cover the area
amount of water used is the amount used per 1000 sq ftl
How do you calibrate drop spreaders?
run the equipment over a test area to determine how much material was used
collect granules from tarp into a container and weigh
you can also use a catch basin
application rate per acre = weight of granules collected * (43560/test area (in sq ft))
application rate per acre = weight of granules collected * (1000/test area (in sq ft)
can adjust by speed or changing metered openings
