July 13, 2018
Strawberries: Harvest is slowing down in most of the province after a warm week. Valley Sunset continues to be harvested in eastern Ontario and the first Malwina are being picked in southern and eastern Ontario. The hot and dry conditions continue to be a challenge.
Renovation is ongoing; many growers in Southern Ontario have mowed their early varieties. Assess your fields before renovation for weed pressure to determine if herbicides are needed and if so which herbicides to use. Broadleaf herbicides need to be applied 5-7 days before mowing. Avoid applying herbicides if temperatures are above 25C. After renovation do not apply sinbar in close sequence to grass herbicides. Refer to the NEW Publication 75B Guide to Weed Control Hort Crops for herbicide options.
The earlier you can apply the herbicide (if necessary) and mow your strawberries the better for SWD management- don’t wait for the late varieties to be done harvest. Renovation is also a good time for cyclamen mite control. See below for more information on products and timing for mite management.
Day neutral strawberries are blooming and have green fruit present.
Mites: Keep an eye out for two spotted spider mites and cyclamen mites in your new fields and in your bearing fields before renovation. Now is a good time to manage cyclamen mites, 4-5 days after mowing for renovation. If you have cyclamen mite damage the entire field or at least the entire variety should be sprayed.
- After renovation Vegol crop oil can be applied in a high water volume to ensure thorough coverage.
- Agri-mek is registered for Two-spotted spider mite (TSSM) post-harvest. If you are applying agri-mek for TSSM you will achieve some efficacy on cyclamen mite.
- Apply Agri-mek once there is new growth after mowing, which could be approximately 5 days after mowing. Apply Agri-mek at 225 mL/ha in 750-1000L water /ha, with a non-ionic surfactant at .1-.5%
- Slow down and get thorough coverage of the plants and crowns.
- Apply Agri-mek under slow-drying conditions to improve uptake into the leaves.
- Do not apply sinbar after applying Agri-mek. Wait 5-7 days after Agir-mek before applying sinbar.
- Avoid spreading cyclamen mites to new fields; work in new fields before moving to old, infested fields.
- Check new fields for signs of cyclamen mites. The earlier we identify hot spots the better we can manage mite outbreaks.
- TSSM will cause plants to appear dry and scorched, and can build up rapidly hot weather. Check the lower leaf surface of middle-aged leaves for mites in bearing and new fields.
Strawberry Aphids: If you have not applied an aphid spray in your new fields it is important to protect those fields now before winged aphids fly in. Bearing fields will need an insecticide after mowing and new growth has emerged.
Tarnished plant bugs (TPB): Continue to monitor day-neutrals for TPB. If more than 25% of clusters have TPB nymphs an insecticide is needed.
Potato Leaf Hoppers (PLH): Monitor new plantings and day neutrals for PLH. Consider control if there are 1-2 nymphs per leaf. Choose a product that will control aphids and leafhoppers, such as Sivanto Prime, Assail, Admire, Cygon or Lagon.
Blueberries: Blueberry harvest is underway in southern Ontario and beginning in eastern and central Ontario. If you are controlling Japanese beetles choose an insecticide that will control both Japanese beetles and SWD, such as Malathion and Exirel.
Raspberries: Harvest is underway in most of the province. The crop is looking good but berry size could be an issue if there isn’t adequate moisture. Raspberries are very attractive to SWD so it is important that you keep your fields as clean as possible and maintain a tight spray schedule if possible.
Raspberry Crop IPM: now available! Check out http://www.omafra.gov.on.ca/IPM/english/raspberries/index.html for information on raspberry integrated pest management. This IPM tool includes information on identification, biology, scouting, and management of raspberry insect, disease and disorders. There is also an SWD page for information on biology, life cycle, and monitoring.
Spotted Wing Drosophila (SWD):.
- SWD numbers are starting to increase this week. We have seen an increase in the number of sites where SWD was captured, and an increase in the number of SWD in the traps.
- Stay up to date with SWD catches by following the ONfruit blog for weekly updates: https://onfruit.wordpress.com/
- Michigan and New York are also monitoring for SWD. New York has reported higher numbers this week in a couple counties – up to 67 at one site.
- SWD could be building up in overripe strawberries and wild hosts (wild raspberries, honeysuckle, mulberries).
- Do not leave overripe strawberries in the field; SWD populations can build up in this leftover fruit.
- Mow strawberries as soon as possible after harvest to protect later varieties, raspberries and blueberries. Renovate early strawberry varieties before others if you are still harvesting late varieties. Mowing will help fruit dry up and be less attractive to SWD.
- Ripening fruit needs to be protected in areas where SWD has been caught.
- Plan to apply an insecticide on raspberries and blueberries before harvest begins, and maintain coverage every 5-7 days.
- Pick early, clean and often. If possible, do not spray late blueberry varieties until they are close to harvest. There are limited options for blueberry growers so if you can leave blocks unsprayed until necessary the more options you will have once there is ripe fruit. Fruit is not susceptible to SWD until it is turning colour.
- Use all forms of management- weekly sprays, regular, thorough harvest (every 2 days or less) and immediate post-harvest cooling to less than 5°C (preferably cooler).
- Don’t spray in temperatures above 27C.
- SWD is more active in the evening and early mornings. Spray from 6-10 am or 6-10 pm if possible.
- Pyrethroid insecticides (MAKO) will not work well in hot weather and will cause an increase in mites. Save the use of this product for later – when weather cools off and mite pressure is low
- This link will take you to an infosheet with the 2018 SWD registrations: https://onfruit.files.wordpress.com/2018/06/registration-for-swd-june-2018.pdf , or check out Ontario.ca/spottedwing, including two emergency use registrations (Mako & Malathion 85 E).
- Research has shown that Assail has some activity on SWD eggs and larvae, but not adults. Assail can be used now to control leafhoppers in day-neutrals.
- It is important for growers to do their own on-farm monitoring to evaluate the SWD status on their farm and their spray program.
The Ontario Berry Grower newsletter: Every other month we send out a newsletter/e-mail to Ontario Berry Grower newsletter subscribers. This e-mail provides links and PDFs to timely articles posted on the OnFruit blog for Ontario berry growers. Some of these articles are also published in The Grower paper. If you would like to subscribe to this service send me an e-mail at Erica.firstname.lastname@example.org.