Soil Water Storage During the Non-crop Period as Influenced by Livestock.

Agriculture has evolved over the decades from simple cultivation to a number of differentiated forms.  Integrating crop and livestock enterprises may be one way to improve agricultural sustainability and take advantage of synergistic effects beneficial to both enterprises.  Our objectives were to determine if over-wintering dry bred cows on cropping systems designed for forage and grain swath grazing influences soil water storage and precipitation-storage efficiency during the non-crop period.  A three-year cropping system of oat/pea-triticale/sweet clover-drilled corn was designed to meet dry bred cow nutritional requirements from November through February.  All phases of the cropping system were present each year.  Soil water content was determined for six years using neutron scatter techniques in 30 cm increments to a depth of 2.1 m.  Treatments for each crop were residue or stover left in place with no livestock grazing (IP), residue or stover removed (R), and all residue or stover grazed by livestock (L).  For 5 of the 6 years, soil water storage and precipitation-storage efficiency was greatest where drilled corn was grown the previous year.  Soil water storage and precipitation-storage efficiency were the lowest for the R treatment.  Soil water content at harvest influenced soil water storage during the after-harvest to fall period.  In most years, greater soil water content at harvest resulted in little or no soil water storage during this period.  Greatest soil water storage occurred during the winter to spring seeding period.  The L treatment was as effective at soil water conservation as the IP treatment even though livestock consumed 50 to 70% of the above-ground biomass.