Optimum seeding date and rate for irrigated cereal and oilseed crops in southern Alberta

High crop productivity is essential for irrigated crops and may be strongly affected by decisions of seeding date and rate. An irrigated field experiment was conducted at two locations in southern Alberta for 4 yr to compare the impact of seeding date and rate on productivity and quality of nine cereal crops and two oilseed crops. Seeding rate was only evaluated on one date in late April or early May, when maximum yields were expected. Delayed seeding reduced crop yields by 0.6 to 1.7% per day after the end of April: flax (Linum usitatissimum L.) <= CWRS wheat (Triticum aestivum L.), feed triticale (x Triticosecale W.) <= CPS or SWS wheat <= triticale or barley (Hordeum vulgare L.) silage <= durum (T. turgidum L.), feed or malt barley