There are some great ideas here, thanks for sharing them. Lawnmower tires would be really handy. I was going to make a foot-wide skirt for the tractor out of hog wire to stop anything like dogs digging near the tractor, and make it so I can flip it up and clip it so the tractor can move... Then unclip it and let it lie on the ground when the tractor is occupied. I think the skirt could easily be made to cover the tires when it's dropped down. So tires would be great. I will check with the lawnmower repair shop to see if they can salvage me a set.
I also really like the idea of carting chickens to the tractor (mass transit!). I have an old garden cart that I can cover with a wire frame. That would be handy, esp. when they are large brooder size. The more I think about it, it's a great idea. My wire dog crate might even fit perfectly into the cart.
In the garden, I want to use the tractor as a mobile fertilizing unit. After they ravage the cover crop, I can till it and the poo under and compost in place. Well, it's the grand plan anyway.
The garden is about 100 x 100 and has an 8' fence. The other possibility if all else fails is to make a frame that fits over my veggie area (it will be about 12 x 24) and let the chickens range all around it. I found plans for a PVC greenhouse frame, which would be very do-able option.
Most of the backyard is just dry rural Colorado weedy stuff... No worries about them harming a turf area. I wish I had the water to grow turf! Alas!!
Cheers,
Michelle