Liquid manure application in Iowa typically takes place in fall after harvest in preparation for the following crop year. Manure is either transported and land applied with tank wagons and/or directly pumped and land applied using a dragline system. Application rate, gallons per acre, is typically controlled by flow control actuators operated by on-board rate controllers which co-process the drive speed, tool-bar width, and the flow meter reading with the operator input of application rate. This system ensures that the desired application rate is achieved for manure application. The manure is supplied to a distribution manifold after it passes through the flow control valve. The manifold is responsible for distribution of the liquid manure to different points on the tool-bar.
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