West central Michigan small fruit regional report – August 23, 2016
Blueberry, raspberry and day-neutral strawberry harvest continues at rapid pace with large volumes of blueberries still remaining in the field.
Michigan’s central region has gone through a series of weather events that provided some relief from the summer drought that affected the area for most of July and August. The amount of precipitation accumulated in the area for the past 15 days was approximately 2.5 to 3 inches of rain. Although this is not enough to meet the hydric need of blueberry fields, it provided a good supply of water and allowed the daily temperatures to scale back to more benign conditions.
Daily temperatures in the area remained high, but throughout most of the week the daily maximum remained below the mid-80s. On average, the daily maximum temperature was 79 degrees Fahrenheit and the daily minimum was 62 F.
Red raspberry harvest continues with excellent fruit quality and very good yields. The only problems associated with this year’s raspberry harvest are related to botrytis fruit rot and spotted wing Drosophila (SWD). For gray mold management, fungicides like Elevate, Pristine and Switch are excellent products with a zero-day pre-harvest interval. For SWD management, removing overripe fruit and harvesting clean on a daily basis combined with insecticide treatments are the best control options. Grandevo and Entrust are good options for organic raspberry production. Also, Delegate and Brigade provide excellent protection against SWD in conventional production. Check the Michigan State University Extension “2016 Fruit Management Guide” (E0154) for doses and other recommended products.
Blueberry harvest is in full swing with Elliott and other late-season varieties being harvested at this time. Fruit harvested for fresh pack and processing is of excellent quality after recent rains and the drop in daily maximum temperatures.
It is important to remember to maintain a strict control of SWD by shortening intervals between applications and repeating the application of insecticide after any rain of more than 0.5 inches. Also, check MSU Enviro-weather for current and advanced weather forecasts before making a decision about when to spray and what product to apply.
For a complete list of recommended insecticides and doses for SWD control, check the 2016 Fruit Management Guide or contact your local MSU Extension office for assistance. You may also contact me at 616-260-0671 or garcias4@msu.edu.