After a cool spring I was beginning to think the ambrosia beetles would never come out. Yes, we have had a few detections around the state that I posted before but we have
captured very few in our traps. In experiments we are conducting no trees have been attacked no matter how unhealthy or stressed. Until today. Yesterday I got a report from the foothills that the first granulate ambrosia beetle was captured. It was 80 degrees in Raleigh yesterday and our traps filled up. This morning we had two attacks at our experimental nursery on Lake Wheeler road. I image when we check tomorrow there will be even more.
Management of ambrosia beetle damage requires pyrethroid applications every 3 weeks to the trunks of trees. Ambrosia beetles usually attack below the first scaffold branches so you do not need to spray the canopy. Most folks apply permethrin with an airblast sprayer. We have tested a manual sprayer and fold more complete, even coverage.
You can read about it in a recent paper. The manual sprayer has two opposing nozzles to quickly cover tree trunk with insecticide. It takes a little longer but uses less insecticide and reduces drift and secondary mite outbreaks.