Control of Peach Twig Borer in Almond, 2018

This study evaluated the efficacy of reduced risk insecticides for control of peach twig borer (PTB). The study was conducted in a second leaf Independence almond orchard near Hickman, CA. Seven treatments were replicated six times in an RCB design, each replicate being a single tree. There was a buffer tree between each experimental tree. The orchard was planted with 22-ft row × 16-ft tree spacing. Materials were applied with a hand-held orchard sprayer operating at 200 psi with a finished spray volume of 50 gal/acre. Treatments were applied on 8 May, 391DD from biofix on 2 Apr. Adult PTB moths were monitored weekly using two pheromone traps, with lures and traps replaced weekly as needed. The number of ‘flagged’ shoots was monitored per tree and removed and dissected for evaluation of PTB weekly for 5 wk from 18 May to 12 Jun. Data were analyzed using ANOVA and means separation with Fisher’s-protected LSD (P < 0.05).

All experimental treatments had significantly lower numbers of flagged shoots on all evaluation dates except for 12 Jun compared with the untreated check. Cumulative flagged shoots were lower in all experimental treatments compared with PureSpray Green horticultural oil, which was also lower than the untreated check. No phytotoxicity was observed (Table 1).

This research was supported by industry gifts of pesticide and funding.