Substituting Water for Herbicides: Interactions of Cover Crop Extent and Irrigation in New York Vineyards 1997
Project Leaders: Robert Pool, Alan Lakso, Richard Dunst
1. Determine the effects of fescue cover of varying widths from zero to complete cover on the growth and cropping of established Concord grapevines with and without supplemental irrigation.
2. Document the basis of vine responses to the treatments (vine growth, yield and fruit quality, water status) over several years of varying weather.
Vine shoot growth (expressed as shoot length) increased as the width of the weed-free zone increased from zero to three feet. Presence or lack of irrigation had no consistent effect on shoot growth in this year of much-above-average rainfall. Measurements of stem water potential showed that the greatest stress occurred when there was no weed-free zone. Shoot lengths were found to be related to stem water potentials in the zero- and nine-foot treatments with and without irrigation, but the effects were not severe. Fraction of floor coverage had a large and significant effect on vine yield. Cover tended to reduce bud fruitfulness and berry weight and to increase fruit soluble solids. Irrigation affected berry growth during the last stages of fruit ripening. Berries on unirrigated vines had the same sugar content as those on irrigated vines, but because the berry size was smaller on the unirrigated vines, the sugar concentration was higher.