Three rates of urea, urea-DCD, and NH₄N0₃ were soil applied in April and August 1986 to strawberry selection OR-US 4930 and cultivar 'Sumas' to determine effects of the nitrification inhibitor dicyandiamide (DCD) and nitrogen source and rate on soil NH₄ and N0₃ levels, fruit yield and quality, and mineral composition...