Tips for Managing OBLR Populations

• Where populations are resistant to organophosphate insecticides and in some cases, also pyrethroids and Confirm, the use of insecticides to control OBLR should be restricted to Bacillus thuringiensis (B.t.) insecticides (Dipel, Foray or Bioprotect) or naturolyte insecticide " Success".
• OBLR has two generations a year in Ontario. Always rotate insecticides between generations, not within generations.
• The overwintering generation of OBLR becomes active in the spring, Look for larva from full pink to petal fall in terminals and flower buds. Larvae will be quite small at first and becomes active when temperatures are above 10° C.
• Apply controls when larvae are actively feeding.
• For the summer generation, monitor moth activity using pheromone traps placed out in mid June and time control for first egg hatch (from 200 -220 DDC at base 6.1° C) after first sustained moth hatch. If using Confirm, the timing is earlier, consult the label for details.
• If using B.t. product the spray solution should be at pH of 7 or less.
• If using Success the spray solution should be at a pH of 6 or more