4.24.13 Mummy Berry Forecast April 24

In all blueberry areas, it has been a slow start to the season.  I do not expect this current rain, which is predicted to last through Thursday, will cause many infections since there are very few mature cups present to produce spores and the majority of the plants are not far enough along to become infected.

Plants are susceptible when their flower buds are at F2 stage, and it is economical to apply fungicide to control mummy berry disease after 40% of the flower buds are at F2. Before the F2 stage, the majority of the flower and leaf buds are protected by hard bud scales the fungus cannot penetrate.  The plants in the majority of areas do not look like they are ready yet. Plants are starting to show flower buds at F2 but none of the monitored fields have more than 32% of their buds at F2 (for bud stages see previous post or the “Mummy berry fungus is getting started Downeast and South” post).

Picture of mummy berry cups showing small pinheads, immature cups and mature cups that would be producing spores.The fungus is also developing slowly in most areas. Mummy berry pinheads have been found in Waldo, Hancock, and Washington counties. Isolated single to a few mature cups were found in Liberty (Waldo County), Pike Brook (barrens) and Blueberry Hill Farm (Jonesboro). The northern most monitored fields we have not seen pin heads yet.

We have nine of our eleven weather stations up.  You can see the data at the UMaine Blueberry weather site, AgriNET University of Maine Blueberry Disease Model Data Dashboard.

If you have a mummy berry site, I would like to hear from you.  Please call me on the blueberry hotline 1.800.897.0757.

If you wish to be added to the email list please send me an email AND if you wish to be added to the Blueberry newsletter email list please fill out the form on the Wild Blueberry Newsletter Request Form page.

– Seanna Annis
sannis@maine.edu