Current products provide inadequate protection from white-tailed deer feeding damage to 'beauregard' sweetpotato

Abstract

With an estimated white-tailed deer (Odocoileus virginianus Raf.) population of over 7 million in the Southeastern United States, deer feeding damage has become a serious problem for sweetpotato growers. Typically, deer feed on foli age during vine growth or dig roots near harvest time. Because of limited information on the efficacy of repellents with sweetpotato, studies were conducted in 1998 and 1999 with several commercial deer repellent products to determine their effectiveness on 'Beauregard' sweetpotato (Ipomea batatas L). In 1998 treatments included Deer Away® (egg-based spray and powder), Tree Guard®, Garlic Barrier®, and thiram. In
1999, Havahart® egg-based spray, Hinder®, Grant's®, XP-20®
(Thiram), and Ro-Pel® were used. Untreated plants were also included in both tests. Damage ratings were taken daily on each plant (0-to-4 scale in 1998 and 0-to-3 scale in 1999). Efficacy was determined by an overall rank sum index. The most effective products in 1998 were Deer Away® powder, Garlic Barrier® at 3x the manufacturer's recommended rate, and Deer Away® spray. In 1999, Havahart® egg spray provided the highest level of protection. No product provided an acceptable level of protection to sweetpotato under the deer pressure in these tests. Egg-based products were most effective and could be used as the basis for the formulation of new products. However, the level of protection provided in the commercial formulations currently registered for other crops is unacceptable to economically protect sweetpotato plants.