When you take a dormant spur sample you may also see peach twig borer hibernacula on the spurs. While you should note the presence of peach twig borer hibernacula in your dormant spur sample, decisions to treat peach twig borer are based on past orchard history and the previous year’s fruit damage sample, not the presence of hibernacula in the dormant spur sample.
If you choose to treat during the dormant season, choose products, such as spinosad, that have minimum impact on natural enemies and water quality. Bloomtime treatments with Bt or other soft insecticides are another good way to prevent water quality problems. The dormant spray alternatives calculator will help you evaluate your options.