Evaluation of the Impact of Residue Baling and Livestock Grazing on Soil Compaction and Crop Yield.

In Nebraska grazing of corn stalks by cattle has been a long standing practice; whereas, baling of corn and soybean residue is a fairly new practice due to the expansion of the ethanol industry in the past 5-10 years. A 20 year research study in eastern Nebraska showed a slight increase in crop yield following grazing compared to no grazing. However, a recent Nebraska producer survey gave an indication as to why 39% of the respondents did not graze their corn residue following harvest. When non-grazers were asked why they did not graze their corn residue, 40% indicated that they felt grazing caused soil compaction. Similar concerns exist for baling operations, since heavy tractors and balers driving across wet soils can also contribute to soil compaction.  A study was initiated in 2013 to determine compaction and subsequent crop yield following a grazing or baling operation compared to no residue removal.  Compaction results from 2014 and 2015 showed a significant increase in penetrometer readings (i.e., measure of soil compaction) following baling and grazing operations at shallower depths. However, none of the treatment average readings exceeded 300 psi, the threshold for impeding root development.  Yields in 2014 for the no removal treatment averaged 11 and 13 bushels higher than the baled and grazed treatments, respectively. Yields from 2015 had the opposite trend with baled yielding 188, grazed 184, and no removal significantly less at 170 bu/ac.