Many farmers question the nitrogen (N)-supplying power of animal manure and apply fertilizer N as insurance against yield losses. Precision farming trials in 2001 add new support for the conclusion that it is not profitable to apply such insurance N when liquid swine manure is injected into soil. The studies were made possible by funding from the Iowa Corn Promotion Board, the Iowa Soybean Promotion Board, and the Integrated Farm and Livestock Demonstration Program through the Iowa Department of Agriculture and Land Stewardship.