5.29.14 Frost and Botrytis risk in Some Areas, May 29

Frost

In Northern Hancock at our Silsby Plains site and at our Deblois and Cherryfield weather station locations in Washington County, there were frost conditions overnight from Wednesday, May 28 to Thursday, May 29.  Lee Beers is a Ph.D. student studying cold tolerance in blueberries and his research has found conditions from 28ºF to 24ºF will cause some minor damage to flowers but temperatures below 24ºF will kill many flowers.  Temperatures at Cherryfield dipped to at least 26ºF and at Deblois and Silsby Plains to dipped to 22ºF for a number of hours. All of the other weather station locations had temperatures above 30ºF overnight.

Botrytis Risk

Two weather station locations, Dresden Mills and West Rockport reported weather conditions that produce a high risk of Botrytis infections IF the fungus is present in a field.   This does not mean fields will get Botrytis, just that there is a risk of infection if the fungus is present.

Fields with mummy berry disease will also have killed blossoms, so please look at the symptoms to determine what has killed your blossoms.  Please take a look at previous blog posts or emails for pictures and descriptions of the symptoms for Mummy berry blight, Botrytis blossom blight, and frost.

Any questions please call Seanna Annis at 1.800.897.0757 (Maine only), or email at sannis@maine.edu.