not just in Iowa

Grew up with it (and continue it) in the Central Valley of Calif.

Our version (Jimmy can verify this) is waving at any dirty (aka) farmer's pickup. You might not know him (probably do), but it's kind a gesture of fellowship (my interpretation). It's more of a thing with my generation and definitely the generation before. The younger guys......not so much. I get stiffed by some of the younger guys. Afraid the tradition might die with them.

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