In this bulletin:
- Crop & Pest Update
- Spotted wing drosophila monitoring
- Tissue sampling
Strawberries: June-bearing season is wrapping up as the last of the Malwina is being picked this week in many areas. Day-neutrals are being harvested. It was great to get rain in many parts of the province this week, although the amount of rain was variable.
Renovation is ongoing in June-bearing fields. Renovate as soon as possible to help manage SWD. Make sure to look for cyclamen mite injury in the fields you are renovating to determine if Agri-mek is needed after mowing. See previous bulletins for comments on renovation.
Day-Neutrals: Spring-planted day-neutrals and overwintered day-neutrals are being picked. Disease pressure has been low but now that there have been a couple rain events with more in the forecast it will be important to maintain regular fungicide protection for botrytis and anthracnose. Include a fungicide for powdery mildew regularly as well. With harvest underway your fungicide options are more limited for anthracnose control- use Switch when anthracnose pressure is high. There are only 3 applications of Switch per year. Other options for anthracnose control are Diplomat and Quadris Top.
Tarnished plant bug: Day-neutral growers need to monitor for tarnished plant bugs, potato leafhoppers and two-spotted spider mites.
- Rimon and Beleaf are good options for TPB as they are easy on beneficial insects but they do not provide much, if any, activity on SWD.
- Cormoran is registered for TPB control with a 1 day PHI and will also provide control for SWD, aphids, and leafhoppers.
Raspberries: Raspberry harvest continues. Pick as clean as possible and spray regularly. The most rainfast SWD products for raspberries include Exirel, group 5s (Delegate, Entrust, Success), and group 3s. Keep your fall-bearing raspberry fields clean as well. If you are not harvesting the early berries try to strip off the fruit to limit the population from building up.
- Japanese beetles are showing up in some fields. Exirel, Harvanta, Malathion, and Up-cyde when applied for SWD will have some activity on Japanese beetles as well
- Viruses: We are also seeing raspberry viruses- in 2016-2017 we completed a raspberry virus survey and found that 36% of fields sampled had more than one virus detected. Watch for virus symptoms in your fields, which could include: vein chlorosis, cupped leaves, crumbly fruit, stunting, weakened plants. Viruses are vectored by aphids, nematodes, or pollen. Monitor for aphids and apply an insecticide if necessary. For more information on raspberry viruses check out: CropIPM Raspberry Viruses
Blueberries: blueberry harvest continues in most parts of the province, and the crop is looking good. Growers are spraying for SWD regularly. Japanese beetles may also need to be controlled in blueberries.
Spotted Wing Drosophila Monitoring 2022- SWD counts continue to increase. All growers with ripe berries should be spraying regularly (every 5-7 days, re-applying after a rain).
Summary of SWD trap catches:
Week traps collected | County/region where SWD was found | Crops where SWD was trapped |
June 11-June 17 | 0 | |
June 18- June 24 | Elgin, Niagara | Wild hosts, strawberries |
June 25- July 1 | Elgin, Niagara, Hamilton | Wild hosts, strawberries, raspberries |
July 2-July 8 | Niagara, Oxford, Middlesex | Wild hosts, strawberries, raspberries |
July 9- July 15 | Elgin, Oxford, Middlesex, Waterloo, Norfolk, Brant, Niagara, Hamilton | Wild hosts, strawberries, raspberries |
July 16- July 22 | Elgin, Oxford, Middlesex, Waterloo, Norfolk, Brant, Niagara, Hamilton | Wild hosts, strawberries, raspberries, blueberries |
To monitor on your own farm you can use sticky cards to identify adults, or salt water tests or plastic baggie tests to monitor for larvae in fruit. Spraying for SWD isn’t necessary until there is ripe fruit present + SWD is active in your area. Do not count on sprays alone– use as many of these tools as possible through the season to control SWD:
- Spray every 5-7 days.
- Using the best products first will help knock the population back down at the beginning of the season. The most efficacious products include Exirel, Delegate, Success, Harvanta and Cormoran.
- Reapply after ½ inch of rain.
- Use products from different groups.
- Spray in the morning (6-10am) or in the evening (6-10 pm) when SWD is active.
- Do not spray in temperatures above 25C.
- Pyrethroid insecticides (Mako, Up-Cyde) will not work well in hot weather and will cause an increase in mites. Save these products for later when weather cools off and mite pressure is low.
- Keep your fruit picked regularly and clean- this can be very effective!
- 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.
- Renovate June-bearing strawberries as soon as possible.
Tissue sampling:
- Late-July to early August is a good time for tissue sampling for a nutrient analysis in strawberries, raspberries and blueberries:
Calendar date | Crop | Plant part sampled | Approximate number to collect |
Late July | Raspberry | Fully expanded leaves from fruiting cane | 100 leaves throughout sampling area |
Late July-early August | Blueberry | Mature mid-shoot leaves of current year growth | 100 leaves throughout sampling area |
Early August | Non-fruiting strawberry | Fully expanded, recently matured leaf -discard petiole immediately | 50 leaves throughout sampling area |
A complete list of the foliar nutrient sufficiency range for fruit crops (apple, berry, grape, tender fruit) can be found at: Table 3. Nutrient Concentration Sufficiency Ranges for Fruit Crops
Where to Send Samples:
Several Ontario commercial testing laboratories can provide you with leaf analysis. Their contact information can be found on the OMAFRA website. For additional information assessing nutrient needs in fruit crops refer to Soil Management, Fertilizer Use, Crop Nutrition and Cover Crops for Fruit Production.