Reducing Deer Damage in 25 Acre Demonstration Vineyard Using Plantskydd Deer Repellent Spray

Name: Charles Schembre, Vineyard Conservation Coordinator  Napa County Resource Conservation District.

Location: Los Carneros, California

Overview: The Napa County RCD Huichica Creek Sustainable Demonstration Vineyard is adjacent to a stream rehabilitation project that has supported an increasing number of deer in recent years. The deer cause the most significant damage by feeding on emerging fruiting and vegetative buds and will continue browsing on tender vegetation late into summer. The deer bed nearby and pose a constant threat.

Timing of Application: A rain event delayed the first fungicide/Plantskydd application. I witnessed some heavy browsing during that period and will definitely err on the side of spraying earlier next year. After the first application, deer browsing essentially stopped, and deer tracks could still be seen all over the property. I decided to spray only 2 of 3 prescribed Plantskydd applications, as the deer were only browsing shoots hanging out of the treated canopy at the edge of the field. This late damage was insignificant. Notwithstanding the facts that harvest was poor for the region, and that there was damage prior to the first application, my feeling is that the product provided good deer browse protection in the vineyard.  Again, I plan to begin spraying earlier next year, when the shoots are in the 2” range if possible.

Tank Mix: Both applications were made using Sulfur DF @ 2 lbs / acre, Badge-X2 @ 1 lb / acre, Wilbur Ellis R-56 spreader / sticker @ 4 oz / acre, Plantskydd Powder Concentrate @ 3 lb / acre, and 50 gal / acre.

Full report and pictures here:  2016 Napa RCD FT Results PDF