Field experiment was conducted on Shano silk loam soil at Othello Research Farm of Washington State University.  Soil sample was taken and analyzed for N, P, K, S, B and Zn. Fresh cut wheat stubble was disked and rototilled into the ground before seedbed preparation.  Fertilizers were added to 112 kg N and 56 Kg P₂ O₅ before herbicide application.  Trifluralin was applied at the rate of 1.12 kg a.i. per ha and was incorporated into the top 7.5 cm to control weeds.  The ground was then packed and pre-irrigated.  Four winter canola Inca, Rapier, Athena and Ericka were seeded on Sep 2, 2005 with 4 replications.  All plots were irrigated twice before the winter.  All cultivars were germinated in 7 days after planting.  Inca was slower in growing than the other 3 lines.  This winter was so dry and no snow cover when the temperature reaching as low as-12 C.  All cultivars survived the winter very well.  CV. Rapier was set back behind other 3 cvs. Irrigation treatment was set on May 3 when the full canopy was developed.  Amount of water applied and soil moisture will be monitored until the pods turn brown.  Plant will be harvested at each level of water application for yield, oil concentration and soil N residue.