Using chemicals

Choose the correct answer for each of the following questions on chemicals.

1. What herbicide do you think the supervisor would choose that is non-residual, will kill weeds that have just germinated, and works by translocation?

   Choose from: Diquat, glyphosate, chlorsulfuron.

   Answer: The correct choice is glyphosate. This herbicide is also non-selective in the weeds it kills. Diquat is a contact herbicide and chlorsulfuron is a pre-emergent herbicide used to kill seeds and storage organs before they germinate.

2. 
   

3. What do you do if the spray stream from a pressurised backpack sprayer spurts out the nozzle?

   Choose from:
   1. Pump the handle to increase the pressure in the tank.
   2. Check for leaks, particularly in joints and seals.
   3. Release the pressure from the tank and clean the line.
   4. Blow or suck on the nozzle to clear it and the line.

   Answer: The correct choice is to release the pressure from the tank and clean the line as spurting indicates a blocked line (Choice iii). Take the line apart and clean it out gently with compressed air.

   Increasing the pressure in the tank may cause serious damage to the sprayer. Leaks should have been dealt with before checking the spray stream. You would not get a strong stream from a leaking backpack sprayer. NEVER try to clear the nozzle or line by doing blowing in or sucking on the nozzle! Remember you are using dangerous chemicals with the sprayer.

[ Back to previous page ]