Effect of oat stubble height on the performance of no-till seeder openers.

摘要

A two-year field study was conducted to investigate the seeding performance of two no-till seed openers (disc and hoe openers), as influenced by stubble height (0, 150, and 400 mm) and tractor wheel track under three crops (canola, wheat, and pea). Seeding depth and the seed scattering index were measured for both openers, and the hairpinned residue was measured for the disc opener. The results showed that in the first year, seeds were placed significantly deeper in the soil with a 0 mm stubble height than that in the soil with 150 or 400 mm stubble heights for all the crops. This was also observed in the second year for the pea crop. The 150 mm stubble height resulted in a lower seed scattering index than the 0 and 400 mm stubble heights. Seeding outside the wheel track resulted in a greater seeding depth and more uniform seed placement than seeding inside the wheel track. The difference in seeding depth between the two openers varied with crop type. The vertical seed scatter index was significantly lower for all crops when seeding with the hoe opener. Another field study was conducted on seeding with the disc opener at five sites with different soil and residue conditions. The results show that the amount of hairpinned residue resulting from the disc opener was proportional to the amount of flat residue, and inversely proportional to the seedbed cone index. Hairpinned residue was the major factor which increased the vertical seed scattering..