In this bulletin:
- crop updates
- anthracnose management
- SWD update
- SWD management in berry crops
August 3, 2017 PDF available: Berry Bulletin August 3
Crop development: Strawberry renovation is complete in southern Ontario. Spring planted and overwintering day neutrals are being harvested. The summer raspberry crop is finishing up. Blueberry harvest continues and growers are happy with the crop so far.
Blueberries: If you are not monitoring for SWD on your farm with salt water traps it is time to start protecting your crop when the fruit is turning blue. It is important to keep the fields as clean as possible- encourage clean picking in pick-your-own operations.
Raspberries: Summer raspberry harvest is done in southern Ontario. Some growers walked away from the crop a week or two early because of heavy SWD infestation. It is important to continue to manage those fields for SWD if you have fall bearing raspberries, blueberries, or day neutral strawberries nearby.
Make sur your June-bearing strawberries are in good shape for mid-August when fruit bud initiation begins. Continue to monitor for and control aphids in both renovated fields and new plantings to stop viruses from spreading. Aphid control is required season long.
Spring planted day neutrals are being harvest. Growers are finding the day neutrals are starting with a light crop. Anthracnose has been seen in a couple day neutral fields. With the continuing wet weather anthracnose could spread- scout for anthracnose after rain and during warm (20-32C) conditions. Captan, Maestro and Thiram for botrytis will also control anthracnose. Tank mix anthracnose fungicides (Pristine, Cabrio) with a compatible fungicide, don’t spray for anthracnose alone.
Spotted wing drosophila remains the biggest problem for growers. Thick canopies can be challenging to get adequate coverage of SWD. Remember that the insecticides are targeting the adult life stage of SWD, so you need to hit the adults when and where they are active. SWD are most active later in the evening or in the early morning.
If you have ripe fruit it is at risk of SWD infestation. SWD numbers continue to climb and populations will grow for the rest of the summer. Optimal temperatures for SWD are between 20-25C, which is contributing to the high population this year.
SWD management is a combination of weekly insecticides, regular, thorough picking (every 2 days or less) and immediate post-harvest cooling to 5C or cooler. Re-apply an insecticide after a rain to maintain coverage- reapplication is needed after 1/2inch of rain.
Pyrethroid insecticides (Mako) will not work well in hot weather and will cause an increase in mites. Save these insecticides for later when weather is cooler and mite pressure is lower.
Renovate June-bearing strawberries as soon as possible to dry up the remaining fruit, making it less attractive to SWD.
Here are some recommendations for SWD management in all berry crops:
- Calibrate your sprayer. There is no room for error, especially when spraying close to harvest.
- Strip bloom and fruit buds from new plantings which won’t be harvested.
- Keep weeds and vegetation mowed or otherwise controlled in and around the field.
- Cool fruit as soon as possible after harvest and keep it cool.
- Develop a system for managing waste fruit. Whenever possible, fruit should be removed from the field. At the very least, unmarketable fruit should be picked off the plant and dropped in alleys and crushed. Fruit which is discarded from coolers or pack sheds should be sealed up in plastic bins or bags, or buried daily at least two feet deep.
- Get set up to monitor for SWD damage by floating fruit in salt water to look for larvae (Figure 1). For information on the “salt test” see ontario.ca/spottedwing under monitoring.
- Pay attention to nighttime temperatures. Warm nights lead to more SWD activity and more rapid SWD development. Adjust harvest and spray schedules accordingly.
- Make sure temperatures are below 25C before you spray to avoid spray burn.
Coming to a twitter near you: Follow me on twitter @PateErica for updates and berry-related production and pest management information!
On Wednesday August 9th, from 7:30am-10:00am, the University of Guelph and Farms at Work is leading a farm tour showcasing Native Pollinator Habitat on Farms, held at Howe Family Farm in Aylmer. Check out the attached poster or the Eventbrite information: