Erica Pate, Fruit Crops Specialist
June 21, 2019
Strawberries: Day-neutral and row-covered June-bearing harvest continues in Southern Ontario. The first harvest has begun in June-bearing fields that weren’t row-covered in early areas, and will begin in central and Eastern Ontario late next week. There is a lot of bloom still present in June-bearing strawberries, and late varieties are just beginning to bloom. New June-bearing and day-neutral plantings are looking good. In day-neutrals blooms and runners are being cut; continue to remove flower buds and bloom until there are 6-8 leaves.
Insects: Tarnished plant bugs, winged strawberry aphids, and cyclamen mites were found this week.
Tarnished plant bugs (TPB): higher levels of TPB have been found this week in June-bearing fields. Monitor for TPB as long as there is bloom present. Options for control during the green fruit stage are group 3 insecticides (Mako, Matador, Decis), Rimon, Assail, or Beleaf for suppression only. Group 3s can be toxic to beneficial insects so avoid these if there is a history of mites. Rimon and Beleaf work best on early-instar nymphs, and multiple applications of these products may be necessary. Do not spray when bees are active.
Strawberry Aphids: Winged aphids have been found- it is very important to have an aphicide on all new fields at this point. Options for aphids in new plantings include Cygon or Lagon, Admire, Assail, Sivanto Prime, Exirel, Beleaf or Vegol Crop Oil.
Exirel will be an excellent option as an aphicide later in the season in late June bearing varieties when aphids build up. When applied for aphids Exirel will also help control SWD, so this is a good product to use when both SWD and aphids are present. Exirel has a 1-day PHI. Do not tank-mix or make sequential applications of Exirel with Group 11 fungicides, copper fungicides, Captan, Maestro, or Folpan. Do not apply Group 11 fungicides 7 days apart from Exirel.
Cyclamen mites: Some damage can be found in June bearing strawberries, including in Valley Sunset and Malwina. If there is no bloom yet there is still time to apply Agri-mek if needed. After bloom assess any damage and determine if a spray is necessary- if there isn’t much damage and the bloom and fruit are out of the crown and healthy, a spray may not be necessary until after renovation or until next spring .
Disease: Continue to protect your fields during and after bloom. Powdery mildew has been seen in day-neutral fields, as well as botrytis, angular leaf spot, and a bit of Anthracnose in day-neutral and June-bearing fields.
Common leaf spot has shown up in a few varieties (Mira, Valley Sunset). Captan or Maestro, Senator, Group 3s (Tilt, Bumper), and Luna Tranquility can be applied to control leaf spot.
Maintain fungicide coverage during these wet conditions for botrytis. Include broad-spectrum group-M fungicides in your disease management program for botrytis and anthracnose and always alternate fungicide groups. Note that anthracnose resistance to Group 11 fungicides has been identified in Ontario (Carbio, Pristine, Quadris Top). Tank-mix with a Group M product. Do not tank mix Group 11s with Exirel.
Blueberries: are in bloom in central Ontario and at petal fall-green fruit in southern Ontario.
Insects: Petal fall is an important time for cranberry and cherry fruitworm. If this pest has been building up you may need a second insecticide 7-14 days after the first. Disease: phomopsis canker and twig blight can be found in some blueberry fields. Prune out infected canes or apply fungicidess at petal fall. Bravo or Echo, Pristine, Cabrio, Allegro or Aliette are registered for Phomopsis control or suppression. Note that Bravo and Echo have a 54 day PHI.
Raspberries: are in bloom and green fruit is present in the south west.
Insects: Crown borer and raspberry sawfly damage has been found in raspberry fields. Identify crown borer damage by digging up damaged plants (weak growth, wilting leaves). Sawdust-like frass and tunneling is indicative of crown borer larvae. Diazinon can be applied before bloom next year or plan to apply Altacor after harvest or in the fall.
Spotted Wing Drosophila: low numbers of SWD (1 or 2) have been caught at a few sites in Southern Ontario.
SWD will lead to soft, juicy, deteriorating berries with a short shelf life.
Monitor our blog and this bulletin for updates, and plan to include 1-2 extra insecticides this year in late strawberry varieties and summer raspberries if necessary. Monitor your own berries using a plastic-baggie test or a salt water test. Spraying for SWD isn’t necessary until there is ripe fruit present + SWD is active in your area. SWD will not infest unripe berries.
Do not count on sprays alone– use as many of these tools as possible through the season to control SWD:
- Keep your fruit picked regularly and clean!
- Cool fruit immediately after harvest.
- Keep alleys clean- either remove unmarketable fruit or crush it in the alley
- After unmarketable fruit is removed it should be destroyed (disposed of, or leave in plastic bags in the sun).
- Make the environment less favourable to SWD- prune the canopy and manage water to reduce humidity (repair leaking drop lines).
- Calibrate your sprayers now to ensure excellent coverage once you start to spray.
- The list of registered products can be found here on our blog. Inseciticdes target SWD adults- make sure to spray when adults are active, in the morning and evening.
- Using Mako can lead to a mite outbreak. Reserve this product for fields that are in their final year of production.
- More details on SWD management can be found here.
- SWD registrations are posted on our blog here: https://onfruit.ca/2019/06/21/registrations-for-spotted-wing-drosophila-june-2019/
- Check our blog for regular updates and counts
I have a new phone number: call or text my cell phone at 519-410-0624.