I think Kevlar has been in some high end tires now for a few years, so I wouldn't be surprised if it found it's way into tractor tires considering the cost of a flat.. but,I found this a bit entertaining..
tough corn?
http://www.infowars.com/kevlar-tires-now-required-to-traverse-spear-like-gmo-crops/Kevlar Tires Now Required to Traverse ‘Spear-Like’ GMO Crops
The website reports that farmers who have opted to plant Monsanto’s genetically modified seeds have run into one daunting problem (outside of decreased yields and an extremely higher risk of disease): little ‘spear-like’ stalks from the harvested GMOs are absolutely wreaking havoc on the heavy duty tractor tires.
Described by one farmer as a ‘field of little spears’, farmers are now turning to kevlar tires. In case you’re not aware, kevlar is the same material used in bulletproof vests to protect from gun bullets.
The stalks are so sharp and weapon-like that they can wreck an entire set of wheels, which is a daunting reality when considered that one tractor can have as many as eight heavy duty tires. Furthermore, a single tractor tire can easily cost thousands of dollars. Thanks to the GMO crops, the average lifespan of a tractor tire has dwindled from five or six years down to just one or two — if the farmer is lucky.
tough corn?