Conventional and organic apple production systems in Sonoma County, CA, were compared in terms of tree growth, fruit yield and quality, biological and chemical nutrient supply, disease and insect pest damage, and economic performance over 4 yr. Management practices for fertility, fruit size, and pests are described. Pheromone dispensers were used in a codling moth mating disruption test. Codling moths caused more damage in pheromone confusion plots than in insecticide-treated plots. Fertility maintenance was easily achieved in both agricultural systems. There were no significant differences in fruit size between the two systems. The organic system was more expensive and more complicated to manage, and higher prices for organically grown fruit were not enough to justify losses, increased management needs, and higher financial risk.