Residue Management to Improve Establishment and Survival in No-Till Canola.

Winter stand loss has been identified over the past several years as a key barrier in no-till canola production in the southern Great Plains. On-farm observations indicated that residue increased the height of the crown of canola plants, perhaps making them more susceptible to injury from cold temperatures and desiccation. Observations of other crops grown in no-till vs. conventional tillage indicated a possible difference in near-surface temperatures (soil and air). The purpose of these experiments is to identify the underlying causes of winter stand loss in no-till canola and to create management strategies to improve winter survival in no-till canola production. The specific objectives are to examine the influence of residue and tillage on stand establishment and winter survival. Treatments include light disking (Conventional), no-till (No-Till), no-till with residue removed (NT-No Residue), no-till with twice as much residue (NT-2X Residue), and no-till with residue burned at planting (NT-Burn). The experiments were established on long-term no-till sites, usually on private farms. Soil temperatures in the seed zone and soil moisture were monitored throughout the winter until bolting in the spring. Winter stand loss, plant vigor at key points in plant development, and other measures of crop development and yield were recorded.

 Initial findings show that residue amount influenced development of canola plants as measured by crown height and fall vigor. These differences were most likely caused by differences in amount of residue and not by tillage because the Conventional, NT-Burn, and NT-No Residue treatments had similar values for residue amount, crown height, and vigor. Canola plants in plots with greater amounts of residue had increased crown height and less vigor.