The effect of metribuzin at six rates of application was evaluated on four soybean (Glycine max L.) cultivars and on common hempnettle (Galeopsis tetrahit L.) over a three-yr period (1985 to 1987). The cultivars Maple Amber and Baron were susceptible to metribuzin whereas the cultivars Maple Isle and KG-20 were tolerant of metribuzin. Metribuzin caused progressively greater reductions in plant stands and loss in yield in the susceptible cultivars as rate of application increased. Metribuzin at 0.5 kg ha-1 or higher controlled over 90% of common hempnettle.

The response of sweet white lupin to several herbicides was evaluated over five years at Charlottetown, Prince Edward Island (PEI) and two years at Cornhill, New Brunswick (NB). Excellent crop tolerance was found to the herbicides: chloramben, ethalfluralin, fluazifop-P, linuron, metobromuron, metolachlor, and trifluralin. None of the above herbicides affected crop grain yield or 1000 seed weight. Sweet white lupin was slightly injured by metribuzin at 500 g ai/ha but yields and 1000 seed weight were not affected. Higher rates of metribuzin reduced lupin yield and 1000 seed weight. Imazethapyr applied POST with 0.25% v/v Agral 90 and 1.0% v/v 28% N fertilizer caused severe crop injury and reduced lupin yields.