The conditions which necessitate hand-ditching are outlined. The proper engineering and digging techniques for the construction of swamp drainage ditches are presented. Shots include: swamps in South Carolina; inspector in a swamp dipping for larvae; putting the larvae in vials for shipment to a laboratory; spray larvaciding on foot; surveying the swamp for ditching; work crews digging drainage ditches; swamp water running through the ditches; intersections of the ditches.
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