Novel Weed Management: Design, Construction, And Evaluation Of Two Inter-Row Cultivation Tools, And The Integration Of Vinegar For Intra-Row Weed Control
Weed management is a constant agricultural concern. Early farmers used hand tools to control weeds. As sources of farm power shifted, with the integration of horses, tractors, and chemicals, weed management tools and techniques evolved in turn. Study objectives were to design, construct, and evaluate two novel cultivators for between-row weed control; and, to integrate vinegar, an organic herbicide, to control in-row weeds. Impetus for new cultivator designs came from designs of antique hand-held tools. The first tool, a block cultivator, has a flat surface which rests against the soil and limits the entrance of a rear-mounted blade. The second tool is shaped like a stirrup hoe with a horizontal steel blade. Block and stirrup cultivators were mounted on a toolbar with a traditional S-tine sweep. The tri-part cultivator was tested in 20 non-crop field events. A multivariable model was created to assess the importance of cultivator design, and environmental and operational variables, on post-cultivation weed survival. Cultivator design strongly influenced weed survival (P less than0.0001). The block provided significantly greater control than the sweeps in 17 of the 20 cultivation events (P less than or equal 0.10). Of 11 environmental and operational parameters, seven effected weed control with the sweep; five impacted control with the stirrup, and only one influenced control with the block. Because of the block cultivator's increased effectiveness and operational flexibility, it has the potential to improve inter-row mechanical weed management. A tractor mounted sprayer was constructed to direct a 25 cm band of vinegar at the base of transplanted broccoli and pepper. Organic paints were applied to crop stems and tested as potential physical barriers to crop stem injury. A single application of 200-grain vinegar (20% acetic acid) at 700 L/ha was applied when weeds had less than six leaves. One day after application, 98% of weeds were killed. The number of germinating weeds two weeks after the vinegar application was less than a quarter of the number which had germinated at two weeks after in-row handweeding. Crop foliage was minimally injured. Neither stem paint prevented stem injury; thus, yields were reduced. More research will be needed to assess alternate stem protectants.
Dissertation or Thesis