To meet future demands for forest products, intensive management practices must be implemented. Fertilization has great potential for increasing production, and it is receiving widespread interest in the timber industry. Helicopters and fixed wing aircraft have been used to broadcast fertilizer in most operational trials to date. Application cost has been a considerable portion of the total cost. Recent experiments using four wheel drive ground vehicles showed that application cost could be reduced considerably. Selective placement of fertilizer and combining operations are also possible with ground vehicles and cost can be reduced even further. Aircraft will continue to be used over difficult terrain and dense, natural stands where ground vehicles cannot operate effectively. The use of ground vehicles will increase, and the lower application cost should accelerate the growth of forest fertilization.
