Fresh bovine manure was mechanically incorporated into loamy sand and silty clay loam Wisconsin soils in April 2004. At varying fertilization-to-planting intervals, radish, lettuce, and carrot seeds were planted; crops were harvested 90, 100, 110 or 111, and 120 days after manure application. As an indicator of potential contamination with fecal pathogens, levels of Escherichia coli in the manure-fertilized soil and presence of E. coli on harvested vegetables were monitored. From initial levels of 4.0 to 4.2 log CFU/g, E. coli levels in both manure-fertilized soils decreased by 2.4 to 2.5 log CFU/g during the first 7 weeks. However, E. coli was consistently detected from enriched soil samples through week 17, perhaps as a result of contamination by birds and other wildlife. In the higher clay silty clay loam soil, the fertilization-to-planting interval affected the prevalence of E. coli on lettuce but not on radishes and carrots. Root crop contamination was consistent across different fertilization-to-harvest intervals in silty clay loam, including the National Organic Program minimum fertilization-to-harvest interval of 120 days. However, lettuce contamination in silty clay loam was significantly (P < 0.10) affected by fertilization-to-harvest interval. Increasing the fertilization-to-planting interval in the lower clay loamy sand soil decreased the prevalence of E. coli on root crops. The fertilization-to-harvest interval had no clear effect on vegetable contamination in loamy sand. Overall, these results do not provide grounds for reducing the National Organic Program minimum fertilization-to-harvest interval from the current 120-day standard.
Evaluation of Fertilization-to-Planting and Fertilization-to-Harvest Intervals for Safe Use of Noncomposted Bovine Manure in Wisconsin Vegetable Production
- Views Icon Views
- PDF LinkPDF
- Share Icon Share
- Search Site
STEVEN C. INGHAM, MELODY A. FANSLAU, REBECCA A. ENGEL, JEFFRY R. BREUER, JANE E. BREUER, THOMAS H. WRIGHT, JUDITH K. REITH-ROZELLE, JUN ZHU; Evaluation of Fertilization-to-Planting and Fertilization-to-Harvest Intervals for Safe Use of Noncomposted Bovine Manure in Wisconsin Vegetable Production. J Food Prot 1 June 2005; 68 (6): 1134–1142. doi: https://doi.org/10.4315/0362-028X-68.6.1134
Download citation file: