Published online by Cambridge University Press: 12 June 2017
Broadleaf weeds, including spurred anoda, emerge after direct-seeded chile peppers are thinned. Field experiments were conducted in 1989, 1990, and 1991 to determine the effect of spurred anoda density on green and red pepper yield, quality, and ease of hand harvest. Spurred anoda was established immediately after peppers were thinned at initial densities of 0, 3, 6, 12, 24, or 48 plants 9 m−1 row. The 1991 experiment also evaluated the influence of delayed pepper thinning and concurrent spurred anoda establishment on the competitive effect of spurred anoda. Spurred anoda were beginning to flower at green harvest and senescing at red harvest regardless of planting date. Spurred anoda were taller and accumulated more biomass when planted at a pepper thinning stage of 10 cm compared to 20 cm. Spurred anoda that emerged after thinning peppers reduced yield and ease of harvest of green and red peppers but not the quality of green peppers. Yield reduction at the highest spurred anoda density was 31 to 49% and 12 to 27% when peppers were thinned at 10 or 20 cm, respectively. Yield reduction was smaller when peppers were thinned at 20 cm tall than 10 cm tall and appeared to be associated with reduced spurred anoda biomass. Time required to hand harvest 1 kg of green or red peppers increased as spurred anoda density increased when peppers were thinned at 10 cm.