Wild Blueberry Newsletter, May 2016
Mummy Berry and Blossom Blight Scouting
Mummy berry disease can cause serious loss of blueberry crop yield by blighting the stems but by the time you see the damage it is too late for control, so if you have had this disease in the past then protective treatments need to be applied to prevent injury. For protective treatment details, see the Wild Blueberry Fact Sheet No. 217, A Method to Control Monilinia Blight and recommendations on the most effective fungicides can be found in Wild Blueberry Fact Sheet No. 219, Disease Control Guide for Wild Blueberries.
Blossom blight disease or Botrytis occurs less frequently in blueberry fields and requires a much longer period of rain during bloom for infection to occur, see Wild Blueberry Fact Sheet No. 212, Botrytis Blight Control for Wild Blueberries, for the differences in identifying and treating this disease.
Information on the progress of these diseases and treatment timings will be sent to growers on our email list. You can also call our hotline for information 1.800.897.0757 x 3 or you can find information on our Wild Blueberry Blog.
Putting out mummy berries in your field will allow you to more accurately monitor the disease and reduce the number of fungicide sprays needed. This method is illustrated in the Mummy berry Disease Forecasting Method on the wild blueberry website. Once the bloom occurs, you should scout your fields to look for blighted stems and blossoms to get an indication of how well your treatments worked and to assess the potential for disease pressure in the next crop.
Wild Blueberry Pollination
With the cool wet spring, we have had this year some growers are considering on diversifying their pollination resources. Although honeybees have contributed to large increases in crop yields over the years, they are not very efficient wild blueberries pollinators but because large numbers of bees can be brought into your fields they are still very effective in pollinating your crop.
Bumblebees are now commercially available and are much more efficient but there are also much fewer bees in the quad. See Wild Blueberry Fact Sheet No. 302, Commercial Bumble Bee (Bombus impatiens) Management for Wild Blueberry Pollination for more details in the use of bumblebees.
There are also a large number of native bees found in and around wild blueberry fields that can provide a significant amount of pollination, see Wild Blueberry Fact Sheet No. 630, Wild Bee Conservation for Wild Blueberry Fields for more details.
How do you know if you have enough bees in your field? Dr. Frank Drummond has developed a simple survey that you can use in your field to determine if you have adequate pollinators. It may be found under Schedule for Monitoring Pollinators in the Wild Blueberry Fact sheet No. 204, Integrated Crop Management Field Scouting Guide for Lowbush Blueberries, Wild Blueberry Fact sheet No. 204, Integrated Crop Management Field Scouting Guide for Lowbush Blueberries and also in the Table on page 28 of your A Pocket Guide to IPM Scouting in Wild Blueberries, 2nd Edition (PDF).
Diversifying your pollination resources will provide you with greater pollination security and ensure you get good pollinati.on even with poor weather conditions.
David E. Yarborough
Extension Blueberry Specialist
Wild blueberry fact sheets, past newsletters, contacts, resource links, calendar of events, and more can be found on the Cooperative Extension’s Maine Wild Blueberries website.
Information in this publication is provided purely for educational purposes. No responsibility is assumed for any problems associated with the use of products or services mentioned. No endorsement of products or companies is intended, nor is criticism of unnamed products or companies implied.
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