This shows one of our quadrats. The sides are numbered to produce a random numbers grid, 20 by 20, for 400 points. When we wished to take a sample we would randomly determine what 10 points we were going to sample in a given plot, and then we would take very small samples from each of those points, about a teaspoon full. Now the nice thing about this is that you never sample the same spot again because you've got 400 points to sample during the course of the study. A composite sample is critical with studying microbes because a centimeter is like going across the Grand Canyon for a microbe. The samples can be completely different. So we find you have to get a composite sample in order to understand what's happening.

This is the rain machine we use for sedimentation studies. We'd go out, climb up the ladder, put the water in and then this machine would rain at a rate of 6 inches per hour. We'd do half hour rains so three inches of rain is what we'd put on the plots. We'd have a little area down at the bottom where we could collect the runoff. From these tests, we'd know just exactly how much soil erodes, and how much runoff occurs. It's kind of a neat thing.

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