Southeast Michigan fruit update for July 6, 2011
San Jose scale crawlers have been found on apple twigs and fruit, and a very high number of cherry fruit flies are being trapped.
As of yesterday (July 5), Jeanette Yaklin, our Genesee area pest management association scout, and myself found San Jose scale crawlers moving about on apple twigs and fruit at several orchards in east Michigan. My colleagues in southwest Michigan reported finding crawlers last week in their part of the state. While both of us have been trapping for the adult emergence, there are years that it is difficult to pinpoint scale crawler activity until we actually find them moving.
San Jose scale is not a new pest to Michigan orchards. However, in the last five years it has been a reemerging pest for apple and peach growers in east Michigan. Many growers have not found that they have had a problem with San Jose scale until they find infected fruit at harvest time.
There are two “windows” of control for San Jose scale. The first and best is a delayed dormant oil application, and the second best time is now when crawlers are moving about. Consult the MSU Extension Bulletin, Michigan Fruit Management Guide, for additional information on insecticide choices for controlling it. There is also a nice article on San Jose scale at the apples.msu.edu website. Lastly, you can consult the trusted reference Common Tree Fruit Pests by Dr. Gus Howitt for detailed lifecycle information. Most of you have this reference on your bookshelf.
In the last few days, we have had very high cherry fruit fly trap catches. Keep an eye on this pest as sweet cherry harvest continues.
Unless new developments occur in the meantime, look for the next fruit crop update this coming Tuesday, July 12 around the noon hour or so.
You can find information on fruit pest management at the News for Agriculture website.