Compaction

When we excavated for the Test Garden, I thought our subsoil was uniquely awful. I don't think it's unique now: not since I helped plant trees in the suburbs. There the developers seem to make a custom of scraping the topsoil off all the lots when they start a new batch of houses. (They sell the dirt to people who need reasonably better dirt than they have: a subject that will come up shortly, for reasons you can guess.) Not content with their vandalism, they run trucks, cement mixers and delivery vans over the subsoil, smashing it to the density of concrete. When they finish a house, they smooth the contours of the lot with a bulldozer and then lay sod over the subsoil. Voila! Ready to move in.

The new homeowner has no idea what's under the sod, but soon finds out. I volunteered in one yard where a sharp, pointed shovel refused to cut the clay below the sod, even when I jumped on the foot rests.