1975 Weed control in lupin investigations

1. The results with pre emergence herbicides confirm previous recommendations of simazine 1.25 kg/ha on heavy soil and diuron 1.25 kg/ha on light soils with the following modification. a) Simazine rates need to be increased to 3 kg/ha on very early (April) sovm crops in southern areas. b) Simazine has not damaged lupins in southern areas and where ryegrass is a major problem on sandy soils (i.e. Esperance) it is likely to give better responses than diuron. 2. As suspected in previous years simazine can by way of effective weed control produce a marked lupin vegetative response without any increase in grain yield. 3. Post emergence herbicides are required for northern areas, particularly for radish control. Basagran and diuron have been shown to be too damaging while simazine and sencor show some promise although they caused damage on sandy soils. 4. With the early April rain the time of seeding x herbicide aspect was not adequately resolved with these experiments. The data should however be of value for comparison with results from other seasons. 75AL21, 75BA5, 75C20, 75E5, 75GE8, 75GE34, 75GE34-2, 75KA6, 75MT5