There will be no regular updates to the IPM message going forward. If something comes up that should be addressed, I will make a special update. if you have any specific questions, please call Hilary at 508-970-7641. thank you and I hope your harvest season goes well.
Cranberry IPM Message
We have been fielding several calls about mixing pesticides. You should ALWAYS do a jar test before mixing a new combination of pesticides in your tank. We have tried Delegate and Callisto and do NOT recommend that combination; it forms clumps and would be a big problem in your tank. People have asked about mixing coppers and Callisto.
Not really much to update this week. It has just been the weather, the weather, the weather. Conditions have been hot and dry and likely some growers are struggling to keep up with the water demands of their vines. It’s important to keep up with the watering to support fruit sizing.
Now is the time to spray for cranberry weevil if you have very high numbers. Contracted migratory honeybees must be pulled out before the Actara spray goes on and bloom should be complete. Actara is extremely toxic to bees, so only spray if you must!
Cranberry Weevil is once again causing big trouble. This week, many growers reported over threshold (9+ in summer) counts ranging from 10-40 count per sweep set on the bog. The only option we have for managing summer weevil is Actara (thiamethoxam). You can NOT treat with Actara if you have bloom on your bog or have contracted pollination services. If you can get the honey bee...
The main items right now are timing of fruitworm sprays and fungicides. The fruit set seems to be coming along slowly. We are just doing our first fruitworm on a piece of Stevens this weekend. Some growers have already done their 2 shots, so it’s very variable out there. Altacor is the best choice. Remember, fungicides can do their best work when applied to FLOWERS...
We have been hearing of reports of uprights exhibiting classic symptoms of frost damage, known as umbrella bloom. In addition to frost injury, umbrella bloom is also associated with insufficient chilling hours; there are also reports of this type of damage from mites or insects, but we have not seen this much in MA.
If you are using pheromone traps for timing management of girdler, black-headed fireworm and/or Sparganothis, you should be monitoring and counting moths at least weekly; more visits may be needed if counts are high. Baits should be changed every 3 weeks.
Pheromone traps to monitor for Spag, BHF, and/or cranberry girdler, should be up.
Timing for Diazinon (or Sevin) treatment is here (or coming up) for Vaccinium scale. Check your bogs. There is a lot of variation among beds. All scale samples that were checked this week showed that egg production has started. For super hybrid samples, crawlers were emerging, and we advised sprays for this weekend and next week.