Aspects of the population dynamics of the weed Alopecurus myosuroides Huds. in winter cereal crops.
See also W.A. 20, 2439 and 2892. Experimental simulation of the theoretical effects of ploughing, both to different depths, and at different times of the year, indicates the optimum methods of cultivation for control of blackgrass (A. myosuroides) populations, and reduction of seed populations in the soil. A technique involving the marking of seed with fluorescent paint, and the recovery of seedlings with seed attached was used to determine the contribution of young seed to future populations. It was shown that about 2/3 of a population of blackgrass is derived from seed less than 1 year old. This proportion would be much lower if the mould-board plough was efficient at burying seeds by totally inverting the soil profile. Plants of A. myosuroides are remarkably plastic, reproductive output varying by at least as much as forty times. Nevertheless some seed is usually set by all mature plants.The spikelets of A. myosuroides may not contain a ripe caryopsis; the proportion wiithout varies between localities and times of harvest. Caryopsis weight is normally distributed around the mean. Some aspects of the dormancy of blackgrass are summarized. From summary.