Trap set up in codling moth mating disruption blocks

Codling moth (CM) and oriental fruit moth (OFM) can both be managed successfully using pheromone mating disruption (MD) as a core component of the IPM program for internal-feeding lepidoptera in Ontario apple orchards. Products for managing OFM alone (OFM: Isomate OFM TT, Isomate Rosso OFM, Isomate M-100 OFM, Semios OFM) or in combination with CM (Isomate CM/OFM TT) are available in Ontario.

Mating disruption for OFM is considered robust, and assuming populations are low, treated blocks are large (> 4 ha) and relatively square, and dispensers are used at the labelled rate, can provide excellent control of this pest in most orchards. In some instances (late maturing apple blocks bordering peach), borders may exhibit a need for supplemental insecticides. Standard traps and lures used in conventional blocks - what we refer to as "sentinel traps" - are used to monitor for OFM in mating disruption blocks. Expect trap shut-down or zero catch (an occasional moth captured in localized border areas is acceptable). For season-long control of OFM, dispensers must be in place before moths start to fly (ideally before bloom), or expect to use an insecticide to manage the first generation*. Note that as of May 13th, OFM have already been captured in some parts of Ontario.

CM is more difficult to disrupt than OFM, and it is common to require some form of supplemental insecticide to manage the first generation (check Pub 360 for products and recommended timings). A different type of pheromone lure system is used to monitor CM in disrupted blocks. Standard 1X lures used in conventional blocks used to establish BIOFIX are replaced with lures designed to trap CM in disrupted blocks (such as Trécé CM L2 lure, CM 10X Megalure, Pherocon CM DA, Pherocon CM-DA Combo). Research indicates that the CM DA Combo lure (contains pheromone and a pear ester - feeding attractant) is the most effective in terms of moth capture MD orchards, and has the advantage of lasting up to 8 weeks. Some growers I have spoken to in 2015 have also been sent an "AA" lure to be used in combination with the CM DA Combo lure, to enhance attractiveness. Use a minimum of 1-2 traps per 4 ha.

CM mating disruption dispensers need to be placed in the upper third of the tree canopy. In MD blocks, traps also need to be placed high in the tree canopy - not at chest height. For ease of scouting, the wire ties on traps can be attached to bamboo or other light poles and hooked over upper branches or wires. Traps should be checked on a weekly basis. The CMDA Combo lures are designed to capture moths in disrupted blocks, so don't be surprised to find them! The numbers captured can be used to help determine if supplemental insecticides are needed. Generally, this threshold is 5 moths in a single trap per week. Do not average trap catches over the entire farm because hot spots are important as a call for action in that particular area. Some growers use a green, yellow and red light system. Trap captures of 0-3 = green; captures in the 4-6 range may be a caution or yellow light; captures of 6 or more would be considered red. Last but not least, make sure to look for signs of holes or failures in the system, whether using conventional and / or MD based management. Check for frass or other signs of CM or OFM feeding. In general, a threshold of 1% damage indicates a need to revise your management program. Monitoring feeding damage during the first generation hatch period, and if you are seeing more 0.5% damage, take steps to modify the program.

"*" Check the label to see how long dispensers last. Isomate M-100 lasts up to 90 days, Isomate-M Rosso lasts up to 120 days, Isomate CM/OFM TT lasts up to 150 days for CM and 90 days for OFM. Insecticides for OFM may be required in late apple varieties where high populations exist.


For more information:
Toll Free: 1-877-424-1300
E-mail: ag.info.omafra@ontario.ca