Pots to Plots: Microshock Weed Control Is an Effective and Energy Efficient Option in the Field

Abstract

Seeking low environmental impact alternatives to chemical herbicides that can be integrated into a regenerative agriculture system, we developed and tested flat-plate electrode weeding equipment applying ultra-low-energy electric shocks to seedlings in the field. Better than 90% control was achieved for all species, with energy to treat 5 weeds m−2 equivalent to 15 kJ ha−1 for L. didymum and A. powellii, and 363 kJ ha−1 (leaf contact only) and 555kJ ha−1 (plants pressed to soil) for in-ground L. multiflorum, all well below our 1 MJ ha−1 target and a fraction of the energy required by any other weeding system. We compared applications to the leaves only or to leaves pressed against the soil surface, to seedlings growing outside in the ground and to plants growing in bags filled with the same soil. No previous studies have made such direct comparisons. Our research indicated that greenhouse and in-field results are comparable, other factors remaining constant. The in-ground, outdoor treatments were as effective and efficient as our previously published in-bag, greenhouse trials. The flat-plate system tested supports sustainable farming by providing ultra-low-energy weed control suitable for manual, robotic, or conventional deployment without recourse to tillage or chemical herbicides.