Northern Research and Demonstration Farm
Livestock feeding operations generate manure that contains plant nutrients useful for crop production. But, as the size of individual livestock operations has increased, so has the size of manure application equipment. Axle loads can exceed 10 tons with larger agricultural implements, including manure tankers. Although fertilizer nutrients within manure aid crop production, such loads can compact soil, thereby affecting crop rooting and, ultimately, yield. This experiment was designed to measure effects of compaction from manure tankers on crop yield. Over a period of three years (1999–2001), each spring, soil was compacted with a manure tanker having a full 6,000 gallon tank; then, each fall, corn and soybean yields were measured to determine effects of compaction on both fall chisel and no-till tillage systems.
Iowa State University
Hanna, H. Mark and Rueber, David, "Compaction from Manure Tanker and Tillage Effects on Corn and Soybean Production" (2002). Iowa State Research Farm Progress Reports. 1654.