Figure 2 in Critical period of weed control in an interseeded system of corn and alfalfa

Figure 2. Interseeded alfalfa dry biomass yield for the first cutting as a percentage of the weed-free interseeded corn and alfalfa control over the critical duration of weedy treatments averaged over corn hybrid (pendulum and upright), for a 2-yr study (2020–2021). Interseeded corn and alfalfa were established in 2019 and 2020 (establishment years), and alfalfa was harvested the following season, in 2020 and 2021. In weedy treatments, weeds emerged with the crop and were then removed at different dates, creating the critical timing of weed removal (green circles).In weed-free interseeded treatments,weeds were added later in the crop, creating the critical weed-free period (black triangles). An interseeded untreated and a weed-free check were included within these treatments. The critical period times are based on a 5% acceptable yield loss and are denoted by the dashed vertical lines, averaged over years and effect of corn hybrid; the boxes denote the SE for each of the growing degree–day estimates. Points represent observed mean values; lines represent the fitted models calculated using the DRC package in R (R Core Team 2020).