A few years ago my brother put stone (I think pea stone or some other small drainage type stone) in a few pheasant pens. It didn't work out well. I don't remember all the particulars, but I think he shoveled it out.
I've always gone with yellow sand. Mound it high in the center of the pens so you don't have water setting after a big rain. You can take a small rototiller in the pens and work it up a couple times a year.
I know I've mentioned putting roofing over pens/outdoor runs and my goal is to have them all covered 100% this year. I'll include some polycarbonate translucent panels
because the heat and the sunlight reduces the [Bird flu] virus. For years I've said when the birds get both cold and wet they get sick and I read a bird flu article that said
hot, dry weather kills the virus. Whether it is something new like bird flu, some type of CRD or other virus/disease it just seems to make sense. I remember reading an article, years ago, about an area in Africa that they claimed had the ideal climate for chickens...both warm and dry for the most part.
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