Spring wheat and durum seeding rates

Irrigated: Residual soil N to 4 feet was 70 lb/acre and residual soil P to 6 inches was 23 ppm. Granular 18-46-0 was applied in October 1996 at a rate of 400 lb/acre. ‘Ben’ durum and ‘McNeal’ spring wheat were planted on 5 May at six seeding rates. Harvest was August 11^th. Maximum durum yield was achieved with a stand of about 1,070,000 plants per acre and maximum wheat yield was achieved with a stand of about 1,500,000 plants per acre.

Dryland: Residual soil N to 3 feet was 112 lb/acre and residual soil P to 6 inches was 46.5 ppm. Liquid N (28-0-0) was applied at a rate of 20 lb N/acre on April 16, 1997. Ben’ durum and ‘McNeal’ spring wheat were planted on April 29^th at six seeding rates. Harvest date was 20 August. Maximum durum yield was achieved with a stand of about 806,000 plants per acre and maximum wheat yield was achieved with a stand of about 220,000 plants per acre.