| Summary: | Wood vinegar, a by-product of wood pyrolysis, is mostly discarded. Wood vinegar has a phytotoxic effect and could be potentially used as a naturally derived herbicide for weed control. The objective of this research was to evaluate the efficacy of wood vinegar from the pyrolysis of apple (<i>Malus</i> × <i>domestica</i> Borkh.) tree branch wastes to control weeds. The wood vinegar concentrations required to inhibit 50% motherwort (<i>Leonurus cardiaca</i> L.), redroot pigweed (<i>Amaranthus retroflexus</i> L.), Spanish needles (<i>Bidens pilosa</i> L.), and tall fescue (<i>Festuca arundinacea</i> L.) seed germination measured 0.51%, 0.48%, 0.16%, and 1.1%, respectively. The wood vinegar application rates (spray volume) required to provide 50% control of motherwort and Spanish needles measured 1911 L ha<sup>−1</sup> and 653 L ha<sup>−1</sup>, respectively, while the highest evaluated rate at 4000 L ha<sup>−1</sup> controlled 35% tall fescue by 10 days after treatment (DAT). Common purslane (<i>Portulaca oleracea</i> L.) control increased as the wood vinegar application rate increased from 500 L ha<sup>−1</sup> to 2000 L ha<sup>−1</sup>. Wood vinegar was more effective in dark than light conditions for controlling common purslane. By 5 DAT, averaged over application rates, wood vinegar provided 95% and 87% control of common purslane in dark and light conditions, respectively. These findings suggest that wood vinegar obtained from the pyrolysis of apple tree branches could be used for weed management.
|
|---|