On-farm energy use is expensive and internal combustion engines further contribute to air pollution.
California walnut growers and processors implement and emphasize technologies that reduce energy requirements and thus costs:
- Minimum or non-tillage: Cultivation impacts soil quality over time and requires considerable internal combustion engine energy, increasing production costs. Walnut growers increasingly turn to selective, non-polluting herbicides to avoid cultivation (see Fig. 11).
- Dehydration Efficiencies: Drying walnuts prior to processing requires considerable heat energy. California Walnut Board research funding supported development of 1) in-bin moisture sensing technology to avoid excessive drying and energy costs (see Fig. 12) importance of enclosing dehydrators in conserving energy resource. (see Fig. 13).
- Irrigation Efficiency: Low volume irrigation systems and use of tree water status technology for precision irrigation, developed through the California Walnut Board’s funded research program, save considerable energy for California walnut growers.
- Off Peak Irrigation: Due to energy costs, many walnut growers irrigate during off peak hours. In addition to grower benefits, this practice conserves energy for public use during high peak hours.
- Other cultural practices that reduce energy
- The IPM program component designed to reduce sprays coincidently reduces grower energy needs.
- California Walnut Board funded research into the trees’ canopy management has developed practices such as every other year pruning directly reducing on-farm energy use.