The degree of leaching of nitrogen, phosphorus, and potassium into soils and permeability of earthen floors within turkey barns

A study was conducted to determine the degree of leaching of N, P, and K and permeability of soils from earthen floors within several turkey barns. Two turkey growout barns and one brooder barn were sampled at specific depths. For each barn, nine 5-ft soil borings were taken from the inside and three 5-ft bores were taken from the outside. The soil borings were divided into five 1-ft bore subsamples representing the top 5 ft of depth and were sent to a private laboratory for the analysis of total Kjeldahl N (TKN), NO₃-N, total P (P₂), K, pH, and percentage organic matter (OM). In addition, Uhland core [1] samples at three depths (1 to 3, 5 to 7, and 9 to 11 in.) were taken to determine soil permeability. The results of this study indicated that significantly greater concentrations of total TKN were present in the first 3 ft of soil depth for the inside vs. outside (control) samples of all farms. However, no differences in total TKN concentration were found between inside and outside samples at the 4- and 5-ft depths. Similar results were found for NO₃-N and K concentrations as noted for total TKN; however, total P₂ concentrations were essentially the same between inside and outside samples for depths of 2 to 5 ft. This finding indicated that total P₂ did not migrate in the soil. The soil permeability results indicated that lower permeability occurred for the inside vs. outside samples at 1 to 3 in. and 5 to 7 in. for all farms averaged together. Thus, this study indicated that leaching of soil nutrients essentially stopped at 4- to 5-ft within these turkey barns, and in addition, soil permeability was lowered by the presence of growing turkeys inside these facilities.