Howdy.
I have a few ideas.
Once in a previous "life" I worked for a pest control company. We used dozens and dozens of these "Ketch all mousetraps". They work really well.
Ketch all mouse traps
The neat thing is that they catch multiple amounts of mice 24 hours a day. They are tin metal traps that you just wind up and put them on the ground around your tractor. My guess, is that 6-10 of them strategically places around your tractor would work fine.
Cost is about $15 each. But you'll own them forever, if you dont run over them!
If you're "cheap" then here's another idea. /forums/images/graemlins/wink.gif
Just take several 1 x 4" pine boards, maybe 1 to 3 ft long and tack nail on about a dozen or more old fashioned Victor snapper mouse traps. Put peanut butter on each trigger and set them. Each morning, just pick up the boards from around your tractor and go to work. Remember those mice dont "fly" up on your tractor. They climb from the ground up the wheels or front end loader, so place the traps near the climbing points.
Reset the little snappers in the evening when you park the tractor. Also, the snapping action of a trap can trigger the other snappers, so maybe you only put one or two on each board, depending on the sensitivity of the snapper. The idea, is just to isolate the trap from the grass so you can find it and pick it up to reset.
It'll work. You'll be amazed at how many you will catch, but eventually, you'll clean out the field populations and get very few. That is what you want!
Last note, if other big vermin are getting in there and snapping the traps, then make some kind of cover so the cats or whoever cant disturb them. /forums/images/graemlins/mad.gif
Cardboard boxes work good.
good luck! /forums/images/graemlins/smile.gif and please post back messages if it works or doesnt work for you!
dwight