Sometimes it does get noisy out in the country, like when the fields are getting sprayed.  Here is a picture of the wheat field next to our house getting sprayed.


This is from my resident farmer, Roy:
"He was probably spraying both fertilizer and herbicide to kill broad leaf weeds.  There are a couple of selective herbicides that kill specific grasses but I don't think that he needed it.  Very rarely do they spray wheat for insects, if they do it is usually an aphid or a mite.  The russian wheat aphid is the most common pest to spray for.  The reason for spraying now is that if they wait to long the fertilizer will cause the wheat to grow too fast and the head will get caught in the boot (part of the plant).  The plant will not develop properly and the yield of the crop will be reduced.  Also if they are spraying herbicide they want to spray as early as possible so the weeds are small and they will not have to use as much chemical.  Chemicals are expensive so farmers will want to use as little as possible."

Spraying has to be done on a day when the wind isn't blowing too much because you could damage your neighbor's field if the herbicides get blown across the road.  It has happened.

This is a picture of the same equipment being used above, just parked.  The sprayer arms are folded in.  Not every farmer has the same kind of equipment.

From Roy again:  "He is using an older four wheel drive Versatile tractor.  He is using radar, mounted on the front of the tractor, to run the meter to make sure not too much or too little is applied per acre.  The sprayer I think has a 120' boom with a 1600 gallon tank.  The nozzles are spaced every 20" so there is overlap just in case one gets plugged."