Spring seedings no-till into soybean, cereal and corn residues have been the most reliable. For spring seeding into sod, kill the sod the fall before, and avoid excessive top growth at spraying time. 15 cm should be maximum, to avoid a heavy matt of dead material, planter hairpinning and too much protection for slugs. Avoid liquid manure application. Summer seeding into sod killed after first or second-cut is not recommended, due to frequent failures caused mainly by slug feeding.
Slugs can completely wipe out seedling alfalfa plants in summer seedings after sod.
This allows the plants to build up root energy reserves and produce sufficient top growth which will hold snow and insulate the overwintering plant. This ensures vigorous spring growth, stand persistence, and reduces damage due to heaving. Cutting during the critical fall harvest period reduces the amount of top growth, thus reducing the potential insulation around the overwintering tissue. The critical fall harvest period is approximately a 6-week period and varies with location in the province. Regional dates for the start of the critical fall harvest period are shown in Figure 3 for alfalfa.