Loeppky, H.A.Derksen, D.A.2018-09-182018-09-181990-02-22http://hdl.handle.net/10388/10687The development of reduced tillage systems and direct seeding systems require the use of herbicides in the fall and prior to seeding to control weeds. A study was initiated in 1988 at Indian Head to examine the effects of 2,4-D amine and 2,4-D amine + dicamba applied in the fall or spring prior to seeding on flax, safflower, mustard, canola, lentil and field pea. Herbicides were applied at the low, high,and double the high rates recommended for use in cereal crops (420, 560, and 1120 g/ha of 2,4-D; and 110 + 420, 140 + 420, and 280 + 840 g/ha of dicamba +2,4-D). Visual crop tolerance ratings, plant populations and yield were assessed in 1988 and 1989. In general, none of the crops tested were adversely affected by faII application of 2,4-D amine alone at up to 1120 g/ha. Spring application of 2,4-D amine alone at 560 and 1120 g/ha caused significant yield reductions in safflower and lentil in 1 out of 2 years but none of the other crops were affected by spring 2,4-D application in either year regardless of the rate. Dicamba + 2,4-D did not cause significant yield reductions in flax, canola or mustard, however, safflower, lentil and pea yields were significantly reduced by spring application of dicamba + 2,4-D regardless of rate and by all but the lowest rate (110 + 420 g/ha) of this mixture applied in the fall.enAttribution-NonCommercial-NoDerivs 2.5 CanadaThe effects of preseeding 2,4-D and dicamba + 2,4-D application on subsequent cropsPresentation