uno, the difference is things that are used only, or primarily, on a road, and things that are used primarily off the road but use the road only occasionally. It's not just farmers; most construction equipment is also exempt.
Truck-mounted fruit loaders, like the one pictured in the attacment, are exempt if they can't go over a certain speed, but if they can achieve highway speeds must get a restricted registration plate (as shown in the picture) which allows them to drive in daylight hours without the normal lights, etc. I'm not certain, but I think the requirment has to do with the fact that police can catch something traveling at 15 MPH, but the faster stuff needs something to identify them if they try to run away. That seems to be the primary reason why any vehicle needs an identifying number plate (other than giving government another excuse to collect another tax).
Also, the only reason why the roads are improved is for the other vehicles you mentioned; the tractors couldn't care less whether the road is improved or not.
In my area, there's at least one large diary operation (MacArthur Farms) which has constructed their own dirt service road alongside the highway. It's kept graded and in good condition by their own equipment, and runs literally for miles between their various operations.
Concerning the comments about road rage and tractors, I think I was always more or less tolerant about tractors, especially if they made an effort to stay near the shoulder and make it easy for others to pass, but I have to admit that since I have gotten a tractor I have gotten even more "friendly" towards the occasional slow-down. I take the opportunity to note what the tractor is and how it's configured...
Truck-mounted fruit loaders, like the one pictured in the attacment, are exempt if they can't go over a certain speed, but if they can achieve highway speeds must get a restricted registration plate (as shown in the picture) which allows them to drive in daylight hours without the normal lights, etc. I'm not certain, but I think the requirment has to do with the fact that police can catch something traveling at 15 MPH, but the faster stuff needs something to identify them if they try to run away. That seems to be the primary reason why any vehicle needs an identifying number plate (other than giving government another excuse to collect another tax).
Also, the only reason why the roads are improved is for the other vehicles you mentioned; the tractors couldn't care less whether the road is improved or not.
In my area, there's at least one large diary operation (MacArthur Farms) which has constructed their own dirt service road alongside the highway. It's kept graded and in good condition by their own equipment, and runs literally for miles between their various operations.
Concerning the comments about road rage and tractors, I think I was always more or less tolerant about tractors, especially if they made an effort to stay near the shoulder and make it easy for others to pass, but I have to admit that since I have gotten a tractor I have gotten even more "friendly" towards the occasional slow-down. I take the opportunity to note what the tractor is and how it's configured...