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 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'.