Berry Bulletin July 12, 2019

July 12, 2019                                                                                            Berry Bulletin July 11

Strawberries:  June bearing harvest continues this week. Valley Sunset is beginning to be harvested and there is green fruit present in Malwina. Renovation is beginning in the south west and southern Ontario in early varieties. Spring-planted day-neutrals are beginning to bloom and overwintered day-neutrals are blooming again.

Insects:  Monitor for tarnished plant bugs, Potato leafhoppers, thrips, winged strawberry aphids, cyclamen mites, and two-spotted spider mites this week. After harvest renovate and mow the plants as soon as possible to reduce SWD populations building up if there are other berry crops or later strawberry varieties on the farm.

Strawberry Aphids & Virus: An insecticide needs to be applied every 2-4 weeks for aphids if you are not monitoring the population. It is very important to control aphids in new plantings as well- there is a low tolerance for aphids in new fields.

• If there are 15 aphids on 60 leaves apply an insecticide.
• Now is a good time to apply Exirel if an aphid spray is needed as Exirel will also control SWD.
• Bearing fields will need an insecticide after mowing and new growth has emerged.
• Cygon and Lagon will provide some control of SWD so will be a good choice if an aphid spray is needed after renovation- this is only necessary if there is other susceptible fruit on the farm.

Thrips: thrips damage continues to be found. Monitor day-neutrals by checking the blossoms and ripening fruit.  Check late varieties and day-neutrals with bloom and ripening fruit for thrips in the blossoms or under the calyx of ripening fruit.

Cyclamen mites: Before renovating check fields for any mite damage. Flag any areas with damage for management after renovation or next spring. Check newly planted fields as well. Mites may be difficult to find where there isn’t much new, succulent growth, but the population will likely build up again in August or September.

If a miticide is needed after renovation:

• 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 Agri-mek before applying sinbar.
• Avoid spreading cyclamen mites to new fields; work in new fields before moving to old, infested fields.

There is limited Agri-mek available so if a spray is needed line up Agri-mek earlier than later. If there is damage the entire field or at least the entire variety should be sprayed.

Potato leafhoppers: leafhopper damage can be found in strawberries and raspberries- causing leaf yellowing and curling.  Monitor for leafhoppers in new plantings, day-neutrals and fall raspberries. Control may be necessary if there are 1-2 nymphs per leaf. In new strawberry plantings choose products that will control aphids and leafhoppers, such as Sivanto Prime, Assail, Admire, Cygon or Lagon.

Tarnished Plant Bug: monitor day neutral strawberries for TPB as they begin to bloom. There is some evidence that Assail will provide some post-infestation control of small SWD eggs and larvae, so Assail could be a good choice if a TPB insecticide is needed and ripe fruit is present. 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.

Disease: Fungicides are beginning to be applied to day-neutrals as bloom begins for anthracnose, powdery mildew and botrytis. Anthracnose infection is favoured by warm, humid weather and splashing rain or irrigation. Choose fungicides from different families and include something for anthracnose- Captan, Maestro, and Thiram will help control anthracnose when applied for botrytis control.

Weeds: During renovation Sinbar should not be applied in close sequence with grass herbicides, Lontrel or 2-4 D. Wait 10-14 days between applications of these products. Herbicides such as Sinbar and Devrinol as pre-emerge products require 1-2 cm rain or irrigation following application.

Blueberries: Harvest is beginning this week in southern Ontario this week, and will likely begin next weekend in central and Eastern Ontario.

The PHI for Delegate to control SWD on blueberries has been reduced through the minor use program. The PHI is now down to 1 day, which should help manage maintaining insecticide coverage with regular picking.

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 later on. Fruit is not susceptible to SWD until it is turning colour.

Raspberries: harvest began this week in southern and eastern Ontario. Fall-bearing raspberry primocanes are looking good.

Insects: Potato leafhoppers can damage new leaves in raspberries, particularly fall-bearing raspberries. Spray before bloom in fall-bearing raspberries if necessary. SWD pressure is increasing. If harvest has begun and SWD is present in your area, insecticides may be needed. Regular thorough and clean harvesting is important for SWD management. See below for more recommendations.

Spotted Wing Drosophila:  SWD has been caught in Chatham- Kent, Essex, Elgin, Norfolk, Hamilton-Wentworth, Niagara, Wellington, Halton, and Northumberland county.

Pressure is beginning to increase and if there is ripe fruit present in these areas it is at risk for SWD damage.  SWD should be managed by harvesting early, thoroughly and often- every 1 to 2 days. Weekly sprays will help keep SWD under control, and in all parts of the province insecticides will likely be needed on late strawberry varieties and late summer-fruiting raspberries. Stay up-to-date on SWD trap catches by following our blog: onfruit.ca.

Growers can conduct salt water tests or plastic baggie tests to assess presence of larvae in fruit.

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).
• More details on SWD management can be found here or in previous bulletins.
• 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 SWD updates and count