Soil Management – Annual meadow-grass
Control of Annual meadow-grass
Annual meadow-grass seeds can be shed throughout the summer in a weedy crop, so there will be many seeds present post-harvest on the soil surface.
The small seeds become incorporated into the soil by natural processes (e.g. earthworms, rainfall). Those that remain on the surface will germinate as they are stimulated by light. Some seeds may be dormant but the level is variable. Germination will decrease if the soil is cultivated.
Having a relatively shallow root system and small seed, this weed is more prevalent in soils with high organic or residual Nitrogen, that have an inherent tendency to form a fine, crumb structured tilth. Seed set by mature plants under the protective canopy of an established arable crop will often germinate quickly once the crop canopy is removed at harvest. Delaying any soil movement after harvest can promote the rapid germination and establishment of seedlings, making stale seedbed techniques more effective.
The application and incorporation of organic materials such as manures, composts and digestates, and any soil disturbance associated with the establishment of cover crops, could be delayed until after the initial post-harvest flush of weeds has been controlled.
Although addressing drainage and compaction issues will have little impact on this weed and its ability to establish quickly in an autumn-sown crop, any soil-related issue that affects crop establishment, development or nutrient uptake will place the weed at a competitive advantage.
While delaying soil management operations can enhance weed control, delaying the establishment of the following crop can have associated yield penalties. Nutritional seed treatments, the application of placement, or starter, fertilisers and the inclusion of nutrients such as Phosphorous in early foliar treatments can be help to minimise this.