West central Michigan fruit regional report – July 15, 2014
Blueberry harvest is in progress with excellent quality and yield. Growers need to be aware of spotted wing Drosophila in blueberry fields, although still in small numbers. Early detection and control are key for successful management.
Weather conditions this past week have been relatively favorable for a good berry harvest for both raspberries and blueberries. Although in some places there were some scattered thunderstorms that left up to 2.5 inches of rain, for most of the week conditions favored good fruit development without the need of supplemental irrigation. Temperatures during the same period were on average 76 degrees Fahrenheit for the daily maximum and 58 F for the minimum temperature.
Summer red raspberries are in full harvest in Ottawa and Kent counties with very good quality and yield. There have been few problems and so far no insect problems have been reported. However, during the past week we caught the first spotted wing Drosophila (SWD) at a raspberry field in northern Ottawa County. Four females were caught in traps loaded with the new TRECE lures. The field was immediately sprayed to contain any early buildup of SWD populations in that field.
Blueberries, on the other hand, are in full harvest in southwest Michigan and in Allegan County. There are fields with excellent quality and good yield. Blueberry harvest at this time includes machine and hand harvest.
In regard to SWD management and control, we found a wider presence of SWD in Allegan County than the previous week. Growers that detected SWD in their fields are applying the recommended insecticides to prevent an early buildup of SWD populations. Continuing with its north dispersal, SWD was found this week in blueberries around Holland, Michigan. However, only one female was detected in a yeast-sugar-baited trap. This detection is a wakeup call for growers in the area to intensify their scouting activities and be ready to initiate its combat as soon as there is fruit at risk.
For growers that are already in full harvest and had SWD detections, Michigan State University Extension would like to remind them to repeat the insecticide application after any rain of more than 0.5 inches. Check the local weather forecast or go to MSU Enviro-weather for the latest weather information before spraying any insecticide against SWD. If rain is in the forecast, use a rainfast insecticide such as Lannate, Mustang MAX, Hero, Imidan, etc. For more options, see “SWD Management Recommendations for Michigan Blueberry.”