|TREATMENT||BULK DENSITY (LB/SQ FT)||SOIL ORGANIC MATTER (%)||SOIL PH|
|0- to 2-inch Soil Sample|
|Compost||65 to 66||5.2 to 5.8||7.4|
|2- to 4-inch Soil Sample|
|Compost||76||3.5||6.9 to 7.0|
Lesson 4: Increased soil P levels…
were significant as a result of three consecutive years of compost manure application and producing increased P movement in runoff and erosion. Application to meet crop N requirements applies more P than is required for crop production. Repeating this practice three years in a row, in addition to applying a high P compost (manure from cattle fed diet with distillers grains), further aggravates this negative environmental impact. If manure is to be applied at a nitrogen-based rate, it is desirable both economically and environmentally to not reapply manure to the same field until soil P levels return to a level requiring additional P supplementation. For some manures with a low N to P ratio, it may be desirable to apply manure at a rate equal to the P removed by the next three to five cropping seasons and then supplement with commercial nitrogen fertilizer to meet crop N requirements. This strategy will produce economic and environmental value, while minimizing the P impact on local surface water. Conclusion Manure’s economic and soil improvement benefits should both be recognized and built into successful cropping systems. Thanks to the work of Wortmann and Walters, we have better insights as to how manure can improve the physical characteristics of soils thus reducing runoff and erosion.
(Source – http://www.farms.com/news/using-manure-as-an-aid-in-reducing-erosion-and-runoff-125894.aspx)