Weed Control Influences Vineyard Minimum Temperatures

¹ UC Cooperative Extension Napa County, 1710 Soscol Ave., #4, Napa, CA 94459-1315
² Dept. of Land, Air, and Water Resources, University of California, Davis, CA 95616.
³ Dept. of Agricultural Botany, University of California, Davis, CA 95616.

In a field experiment, post-emergence herbicides, disking, and mowing were used to control weeds between the vine rows in four vineyards, in the Napa and Sonoma Valleys evaluated over a three year period. Herbicide treated vineyards had minimum temperatures 0.3°C to 0.6°C higher than disked or mowed vineyards on most nights during the spring freeze season. Mowed vineyards had minimum temperatures about the same as the disked vineyards on most nights. Vine canopy development did not seem to influence treatment differences, but treatment effects on minimum temperature were greater on colder nights.

Key words: frost protection, freeze protection, herbicides, cultivation, mowing, chemical mowing, living mulches

Submitted on September 20, 1991