Effect of Duration of Green Foxtail (Setaria viridis) Competition on Potato (Solanum tuberosum) Yield

Abstract
The effects of different periods of green foxtail competition on the components of potato yield were investigated. Delaying the removal of green foxtail for 2 wk following crop emergence reduced total and marketable tuber yield by 19 and 29%, respectively, when averaged over 2 yr. Similarly, the number and average weight of marketable tubers were reduced by 24 and 6%, respectively. The proportion of unmarketable tubers comprising the total yield increased as the duration of weed competition was increased. Successively longer periods of green foxtail competition further decreased the measured parameters.