Northwest and Allee Research and Demonstration Farms

Soil and Phosphorus Losses with Surface Runoff from Corn-Soybean Rotations as Affected by Tillage, Cover Crops, and Phosphorus Placement Methods

Authors: Antonio Mallarino (Iowa State University) , Terry Tuttle (Iowa State University) , Mazhar Haq (Iowa State University) , Josh Siever (Iowa State University)

Abstract

Research has shown that no-till greatly reduces soil loss from surface runoff compared with tillage. Although no-till often reduces sediment-bound phosphorus (P) loss, it can increase the proportion of dissolved P in runoff or the amount lost. There is little information about how broadcast or subsurface banding of P influences P loss with runoff. Subsurface P banding with the planter may reduce P loss mainly from no-till fields because it should reduce the P accumulation in the soil surface layer. In Iowa and the Corn Belt, most farmers broadcast P in the fall (when the risk of runoff events is small) or band P with planters. The objective of this study was to evaluate soil and P loss with surface runoff in corn-soybean rotations as affected by the tillage system and these two commonly used P application methods.

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How to Cite: Mallarino, A. , Tuttle, T. , Haq, M. & Siever, J. (2019) “Soil and Phosphorus Losses with Surface Runoff from Corn-Soybean Rotations as Affected by Tillage, Cover Crops, and Phosphorus Placement Methods”, Iowa State University Research and Demonstration Farms Progress Reports. 2018(1).