Effects of Clover Cover Crops and Poultry Litter On Pecan Orchard Soil Microbial Activity

Little information is available regarding the activity of soil quality biological indicators in southeastern U.S. pecan orchards. The objectives of this study were to examine the effect of poultry litter application and the use of crimson clover as a cool season cover crop on soil chemistry and soil quality biological indicators in a southeastern U.S. Coastal Plain pecan orchard system. The use of clover as a cool season cover crop between tree rows provided multiple benefits for pecan orchard soil quality, including increased MIP and MBC.  Soil phosphatase activity was also enhanced by clover during two of the three years of study. Soil elemental properties, including total nitrogen (N), and soil organic matter (SOM), were also enhanced by clover and/or poultry litter, although there was an obvious time lag in the response of soil N to the treatments. Poultry litter application increased soil phosphorus (P), but did not consistently enhance soil biological activity parameters. At times, poultry litter appeared to neutralize or minimize the positive effects of clover on MIP.