The use of herbicides in vineyards has been a cost-effective means of in-row weed management under the grape canopy. However, as public concerns about issues such as pesticide run-off, ground water quality, and soil erosion have increased, grape growers have become aware of a need for alternative methods of weed management. The overall objective of this project was to identify optimal weed management practices that maximize grapevine growth and development as well as vineyard soil quality.
The Iowa wine and grape industry underwent a rapid phase of growth at the turn of the 21st century that is continuing to evolve and develop today. Cultivar trials across the state found that `Marquette' grapevines were performing poorly in eastern Iowa while other cultivars performed well. A preliminary investigation suggested a magnesium induced potassium deficiency and/or above optimum soil pH as the cause of poor growth of `Marquette'.