Massachusetts IPM Berry Blast
June 19, 2015
Spotted Wing Drosophila UPDATE
Trap monitoring for the 2015 season began this week with no SWD caught in any traps. A paired trap system is being used at each site with one trap using Suzukii Bait
and the second trap using a commercially available Pherocon trap w/ a 3-component lure
and soapy water. Effectiveness of each of these trap systems is being evaluated. We will monitor all traps weekly for the remainder of the season and send out updates on Friday afternoons.
Below are the basic recommendations for SWD management for 2015. In addition please refer to https://extension.umass.edu/fruitadvisor/spotted-wing-drosophila/management
Basic recommendations for SWD management:
- Keep rows of raspberries narrow at the base (18") and thin canes to allow 6" between canes if possible to allow for good air circulation and light penetration. In blueberries, eliminate branches below knee high (on mature bushes) that cast shade on the ground and open the upper canopy to allow for good air circulation and light penetration. This will improve spray penetration and efficacy, too. In other berry crops, maintain an open canopy as much as possible
- Growers should set out and monitor traps in their fields to know what is happening on their farms by mid June or before susceptible fruit begins to color.
- Remember to harvest frequently (daily if possible), and thoroughly and avoid allowing fruit to fall to the ground if possible.
- Transport harvested fruit as quickly as possible to refrigeration.
- Spray recommended materials (organic or conventional) on a tight schedule (5-7 days) once crop is ripening and SWD have been confirmed at or near the crop. Some recommend spraying in the evening to increase residual efficacy because some materials degrade more quickly in sunlight. SWD may also be more active in the evening especially when the weather is very hot. Also, it is recommended to add 2# of sugar per 100 gallons of spray solution to all materials except pyrethroids (which don't show increased efficacy from this addition).
- Sample fruit regularly during harvest and do salt flotation test to determine SWD larval presence and density.
While information derived from our monitoring network is designed to help growers know the general status of SWD in their region, it is still important for farms with susceptible crops to monitor populations locally in order to properly time the start of any spray program. The combination of onset of ripening fruit plus a positive trap find marks the start of a spray program. Without a positive trap find, unnecessary sprays may be made shortening the useful life of certain materials that have limits on the number of applications that can be used.
Archived IPM Berry Blasts are available at the UMass Extension Fruitadvisor website.
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