chickens
shed & run design
chicken tractors
A chicken tractor is a hutch or a very small chicken coup designed to be  moved on a regular basis.  They usually have wheels on one end to assist in moving, though some smaller chicken tractors have handles  so they can be picked up and carried by two people.

chicken tractor management
A fairly large area is needed to run a chicken tractor, either a large lawn or meadow or a big enough vegetable patch to allow you to always have some fallow ground available for the chicken tractor to sit on.

When used in a meadow a chicken tractor is usually moved either on a daily basis or every two or three days.  This gives the chickens enough time to mow the grass down but not long enough to scratch it all up.  Some chicken tractors used to crop grass in a meadow have wire at the base of the tractor to stop the chickens tearing up the ground and as an added protection against foxes.

When used on fallow ground in a large vegetable patch a chicken tractor is left in the one place for however long a time the ground is being fallowed, this could be anywhere from a few weeks to several months.  Chicken tractors used on fallow ground usually do not have wire at the base as the chickens need to be able to scratch at the ground in order to turn it over.

advantages/disadvantages summary
Photo of a home made chicken tractor with wheels at one end.
Homemade chicken tractor with wheels at the back and handles at the front so it can be moved easily.  Image courtesy of the internet.
Photo of a small homemade A frame chicken tractor.
Small homemade A frame chicken tractor similar to the one I used to have.  It has handles at both ends so it can be picked up by two people.  Image courtesy of the internet.
Photo of a large commercially made chicken tractor.
Large commercially made chicken tractor designed for at least six chickens.
Advantages
  • A good way to manure a meadow or a vegetable bed that is being fallowed.
     
  • Minimises disease risks as the tractor is constantly being moved to fresh ground.
     
  • When used on a fallowed vegetable bed it does a good job preparing that bed as the chickens will weed and turn the soil over as well as manure it.
Disadvantages
  • Difficult to clean as an adult cannot stand up inside them.
     
  • Cost as much or even more than larger walk in chicken coops.  This is because the designs are usually more intricate than standard rectangular shaped coops
     
  • If made of wood they offer plenty of cracks for spider mites to hide in.
     
  • Generally only suitable for two or three small to medium sized hens.  Though there are some quite large chicken tractor designs around that could run up to six chickens.
     
  • A chicken that is being henpecked by another dominant chicken will have no space to escape to.
     
  • Not suitable for a rooster.
the chicken tractor i had
The A frame chicken tractor (centre right photo) is pretty similar to the chicken tractor I had for a while.  Unfortunately I built in the era before digital cameras and I neglected take any photos of it.

I made mine to specifically fit on my raised beds.  I used it on fallowed beds for a while but I soon realised that my vegetable patch was not big enough to have a part of it left as fallow ground.  I eventually dismantled it.  Though at the time it did serve it's purpose well.  If I was to make another chicken tractor I would make it out of much lighter materials as I found my original design to be too heavy.

Conclusion
Chicken tractors are much more practical than chicken hutches as their portability offers a niche that conventional chicken coupes cannot cover.  If you have a big enough vegetable garden that you can fallow part of it on a regular basis or have a large lawn or meadow then a chicken tractor is definitely worth considering.