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My six Plymouth Barred Rock chickens are about 8 weeks old. They seem happy in their coop, but I feel sorry for them when I see them futilely scratching around in the wood shavings that are bereft of tasty grubs, beetles, worms, weeds, and seeds. I want to let them roam around freely in my yard, where they can aerate the soil, gobble the weeds and vermin, and fertilize the grass. But I think they're still too young and small to let loose in the yard. For one thing, a couple of semi-wild, semi-friendly cats like to visit our cats and kids regularly, and I don't think my young hens would stand a chance against them. Also, even though our property is completely fenced in, the chickens are still small enough to squeeze through openings.
After a little research, I came across two solutions that would allow the chickens to safely spend their days in the yard. One is electric net fencing — a kind of mesh that has fine exposed wires woven into it. You can move it around anywhere in the yard, and the shock it delivers will keep the chickens in and the predators out. According to Harvey Ussery, the "21st Century Homesteading" columnist for Mother Earth News, electric net fencing "carries an unpleasant (but not harmful) surprise for unwelcome curiosity seekers." I don't like this idea, partly because I don't want to be the cause of animals receiving shocks, but mainly because I'm certain I'd be the frequent recipient of "unpleasant surprises" from coming into contact with the fence while it was activated.
The second solution, a chicken tractor, was much more appealing. These are basically portable pens without a bottom that you can move around to different spots in your yard so your chickens can eat all the scary bugs crawling in the grass and dirt. This seems like a good solution. The top hit on Google is a gallery of 140 chicken tractor photographs, compiled by Katy of The City Chicken. It's neat to see all of these hand-made tractors. No two are identical. Many are made from salvaged materials.
(The tractors remind me of the coconut scrapers I came across in Rarotonga. Everybody made them from scratch and so they were all different, reflecting the skills, patience, and temperament of the maker.)
After perusing the photos in the gallery and using Amazon's Look Inside! feature to read a portion of Andy Lee and Pat Foreman's book, Chicken Tractor: The Permaculture Guide to Happy Hens and Healthy Soil, I went to work designing my own. I liked the A-frame style the best, because it seems easier to make and more stable than a box-shaped tractor.
This was a good excuse to get acquainted with Google SketchUp, a free application that lets you create 3D models. I downloaded it and watched a few of the training videos, which were enough to get me to the point where I could design a humble tractor. My goal in designing the tractor was to come up with something that was very basic, used as few components as possible, used as few different dimensional-sizes of lumber as possible, and provided a comfortable and shady shelter for my hens. Here's what I have so far.
(It will be made from lumber and plywood. The open areas will be covered with 1/2-inch wire screen.) You can download the Sketchup file here.
If you have any suggestions of how I can simplify or improve my design before I start building it, I would be grateful to hear them.