In this bulletin:
- Crop & pest update
- Spotted wing drosophila
- Herbicide resistant weeds
- What’s Growing ON? Podcast
Mid-season varieties are beginning to be harvested. There is a good demand for berries and pick-your-own is going well with a lot of interest from customers. Although the early varieties were a bit small at the beginning of harvest, mid-season varieties are looking good with a good yield. Valley sunset is beginning to ripen and Malwina bloom is finishing. Some areas are getting dry although there were a few welcome rains over the last week.
New plantings look variable, which could be due to the planting conditions and how quickly they were planted.
Day-neutrals are beginning to bloom. Remove runners every couple of weeks; these are taking energy away from the plant.
Insects: Insect activity has been low this week but continue to monitor for tarnished plant bugs in late varieties and day-neutrals, cyclamen mites, two-spotted spider mites, potato leafhoppers and aphids. Thrips pressure has been low at this point.
Potato Leafhoppers: Leafhopper nymphs and hopper burn (leaf curling and yellowing) have been found in day-neutral fields. Monitor for nymphs on the underside of leaves in new fields and day neutrals. Malathion, Assail, and Cormoran are registered for control.
Two-spotted spider mites: Spider mites are building up in day-neutrals and June-bearing strawberries in some areas, but pressure is variable. Nealta, Oberon, or Agri-mek can be applied for control before harvest.
Aphids: Winged aphids have been found at a few farms. Don’t forget about protecting your new fields from virus- aphids need to be sprayed every 2-4 weeks if you aren’t monitoring.
Slugs: Slug damage has been reported at a few farms approaching harvest. Although it has been dry slugs can be a challenge where fields are irrigated or where frost protection was used. Irrigate early in the day so plants can dry by the evening. Sluggo can be applied right up to harvest, or Deadline has a 6-day preharvest interval.
Powdery mildew infections can be found in over-wintered day-neutral fields. Check the lower leaf surface for white patches of the fungus. Once powdery mildew is found begin a regular spray program.
Reports of anthracnose and botrytis continue to be low but more infections are beginning to show up. Protect your day-neutral fields during and after bloom. Anthracnose is a threat when there is warm and rainy weather. Choose products for botrytis that will also control anthracnose, including Captan, Maestro, Switch, Pristine, and Diplomat (suppression only of botrytis). Tank-mix group 11 products with a Group M product for resistance management.
Reminder of these Anthracnose Management Suggestions 2020 (more details attached):
- Apply Bravo or captan before bloom for botrytis control.
- As much as possible apply broad spectrum fungicides (group M) during bloom.
- During harvest your options are more limited because of the longer REI and PHI intervals. Options include Switch, Diplomat, Quadris Top.
- Do not rely on group 11 products alone.
- Clean up diseased fruit and remove from field.
- Nitrogen management is very important. Avoid over-application of nitrogen.
- The source of nitrogen can also have an effect; avoid ammonium forms of nitrogen.
- Don’t let the plant canopy get too thick.
- Sanitize between fields (eg. equipment, tools, hands).
- Work in older fields, and/or diseased fields last.
Raspberry harvest has begun in the southwest and will begin in southern and central Ontario in the next 1-2 weeks. Primocane fruiting raspberries are looking good.
Watch for two-spotted spider mites (TSSM) building up in tunnel and field raspberries. Kanemite, Acramite, Oberon and Kopa can be applied before harvest for TSSM control.
Watch for potato leafhoppers in raspberries, especially primocane fruiting raspberries. Monitor for nymphs on the underside of leaves in new fields and day neutrals. Spray when nymphs are present and symptoms are evident.
Blueberry harvest will begin in the next 7-10 days in early areas and the crop is looking good.
Spotted wing drosophila:
Spotted wing drosophila (SWD) has been identified in Essex, Kent, Norfolk, Elgin, Niagara, Oxford, & Halton. The counts this year are similar to 2017, which was an early and challenging year.
For strawberry growers:
- Late season varieties could be at risk, depending on how quickly SWD populations develop.
- Encourage clean picking.
- Renovate as soon as harvest is complete. Do not wait for late varieties to be harvested to renovate earlier blocks.
- Overwintered day-neutral fields are more at risk compared to new plantings, because extra foliage and plant debris in older fields make clean harvest more difficult. As you drop fields at the end of the season, mow them or do something to destroy fruit.
Summer fruiting raspberry growers may also need to spray for SWD this year.
Check the Onfruit.ca blog for full details on counts which will be updated weekly.
Spraying for SWD isn’t necessary until there is ripe fruit present + SWD is active in your area.
Suspect you have herbicide resistant weeds?
Participate in a genetic testing sampling project. Do you suspect that you have herbicide resistant weeds on your farm? If so, why not get them tested for free through a genetic testing sample project. So far there are 16 (5 more in progress) genetic quick tests to assist in identifying herbicide resistance in 12 weed species. Some of these tests were implemented from scientific literature. Two are new discoveries. These tests deliver a diagnostic and a recommendation to the grower within the same growing season.
For more information read the 2020 June Genetic Testing for Herbicide Resistant Weeds (002) article or contact Kristen Obeid for sampling collection kits and sampling protocols: Kristen.firstname.lastname@example.org, 519-965-0107.
What’s growing ON? Podcast:
Check out the new podcast What’s Growing On? For an episode with Hannah Fraser (OMAFRA Entomologist) and I that covers different SWD management practices for berry growers. This podcast also includes episodes from other crop specialists, including vegetables, apples, and tender fruit. All episodes can be found under the Podcast tab on the blog homepage or at onfruit.ca/podcast.
You can also search for episodes on your favourite podcast app including Apple Podcasts, Spotify and Google Podcasts.