Control of selected perenial weeds with glyphosate.
Glyphosate was evaluated for the control of 5 perennial weed species on sites throughout North Carolina. Rates of 1.1 or 2.2 kg/ha applied in mid-June to Sep. controlled blackberries (Rubus sp.). Mid-Aug. application of 2.2 kg/ha controlled 83% of actively growing Lonicera japonica, while this rate applied from mid-June to mid-Aug. gave 87% control of Toxicodendron radicans. Consistent control of Lespedeza cuneata was obtained with 1.1 or 2.2 kg glyphosate/ha at flowering, while these rates applied from late July to early Oct. gave at least 50% control of Campsis radicans. The addition of 0.5% v/v wetter to glyphosate had no effect on the control of the weeds studied.