Early Season Corn Development in a Kura Clover (Trifolium ambiguum Bieb.) Living Mulch

Abstract

Kura clover (Trifolium ambiguum Bieb.) perennial living mulch has many agronomic and ecological benefits, but corn produced in this system is often lower yielding than monocrop corn, and this yield loss is often preceded by delayed emergence and development. To prepare rows for corn production, kura clover is selectively killed in strips using mechanical or chemical means. We monitored kura clover health, soil moisture & temperature, corn emergence, corn development, and corn yield in four row preparation strategies: herbicide band kill (BK), shank tillage (ST), novel rotary zone tillage (RZT), and dual tillage (DT) which consisted of shank tillage followed by rotary zone tillage. Our primary objective was to compare novel RZT with the traditional strip tillage unit (ST). In 2015, corn grown in RZT plots emerged and developed faster than corn grown in ST plots, but this did not lead to a difference in grain or stover yield. In 2016, corn grown in RZT and DT plots emerged and developed faster than corn grown in ST and BK plots, and grain yield in 2016 was higher (P=0.05) in the RZT and DT (10.9 Mg ha-1 and 11.6 Mg ha-1) than in the ST and BK treatments (6.9 Mg ha-1 for both treatments). Kura clover biomass was not affected by treatment in either year. Based on these results, rotary zone tillage is a promising row preparation strategy in kura clover living mulch for corn production with minimal herbicide use.