Codling Moth Orchard Sampling Protocol Wendy Jones WSU - TFREC Wenatchee, WA

Background  After interception of 3 codling moth larvae Taiwan mandated a stricter protocol for screening lots for larvae to lift suspension for the remainder of the 2004 crop.  Industry loss $26M  For the 2005 season, Taiwan mandated that we develop and implement measures to evaluate the efficacy of orchard control programs to eliminate high risk lots from being exported to Taiwan.

Supplying Orchard Requirements  Must follow pest control practices recommended by Federal/State Cooperative Extension Service.  Management practices may use: monitoring, degree-day models for treatment timing, chemical controls, biological control, mating disruption, or a combination of methods.  Growers must maintain records of all codling moth management activities and supply records to APHIS &/or BAPHIQ on request.  Growers will be identified by grower lot number on the end panel of each carton packed for Taiwan.  Before any grower lot is submitted for packing, the efficacy of the orchard codling moth control program must be evaluated to eliminate high risk orchards.

Field Evaluation Protocol - 2 Steps 1)Voluntary Initial Screening - Codling Moth Trap Catches 2)Required Codling Moth Damage Pre- packing Evaluation

 If cumulative trap catch in a single CM trap during 2nd & 3rd generations is 30 or more CM per trap in a conventionally treated orchard or 20 CM per trap in a mating disruption orchard, the orchard is considered high risk for export.  Use a large delta trap with a 1 mg lure (1X lure type) for conventional orchard; use a 10 mg lure (10X lure type - e.g. Biolure, Superlure, Megalure) for mating disruption orchard.  Use at least 1 trap per 5 acres; monitor weekly. Voluntary Initial Screening Guidelines

Required CM Damage Pre-Packing Fruit Evaluation 1)On-tree visual inspection using the sequential sampling protocol; 2) Bin sampling alternative: use if on-tree sample not done, or use to re-sampling if needed.

Bin Sampling Protocol fruit per grower lot /variety with no more than 25 fruit from top layer of each bin for 60 bins/lot; -If grower lot is less than 60 bins, sample more per bin; -Must represent all parts of orchard; (or this shipment) -All suspect fruit must be cut; -Over 2 fruit (>0.15%) with a larva rejects orchard; -May be sampled in orchard or at packinghouse; -A person qualified to identify codling moth damage & larvae; (cert. cull cutter or PCO) -Record form must be used.

Sequential Sampling Protocol 1)Blocks chosen for sampling should be reasonably uniform in terms of cultivars, growing conditions and codling moth management program. 2)Any person qualified to recognize codling moth damage in the field can do the sampling. (cert. PCO) 3)Avoid sampling at noon, and don’t sample looking into the sun. 4)Take a break after 4 hours of sampling.

Sequential Sampling Protocol 5)Starting in the portion of the orchard with highest CM density or history of damage, select trees randomly within the area, but separated by at least 70 feet ( paces), working in a grid pattern. 6)Each tree sample will consist of 60 half-fruit.

7) A half-fruit is one where you can see the entire side of the fruit and the calyx. Partially hidden fruit should not be counted. 8) Start sampling fruit at the top of the tree counting each half-fruit and moving down the tree. Sequential Sampling Protocol

9)Continue counting half-fruit as you work your way down the tree. 10)You can move around the tree as long as fruit aren’t counted twice. 11)If there aren’t 60 half-fruit on the tree, its OK to continue to the adjacent tree. 12)All suspect fruit must be cut and examined for live larvae. Record only live larvae as damage.

Use of a pruning pole is recommended to remove suspect fruit for cutting.

Cutting Fruit 13)All suspect fruit must be cut and examined for larvae. 14)Fruit should be cut through the center from stem to calyx. 15)Side entries should also be cut and examined. 16)Record only the number of fruit with live larvae on the record sheet for each tree.

Codling Moth Larvae Codling moth tunnel through the fruit flesh to reach the seeds at the core. In relatively new entries, young larvae may not yet be inside the fruit but are still alive and must be counted.

Sequential Sampling Worksheet  Use of the data recording form is mandatory.  It determines the number of trees required for sampling based on number of live larvae found.  It must accompany the 1st shipment of bins to the packinghouse.  The form verifies that fruit come from a Sec.1.4 compliant orchard.

Orchard CM Control Worksheet Here’s how the table works:  The table is designed to determine if the infestation level is greater than or equal to 0.2% (reject) or less than or equal to 0.04% (accept).  The minimum number of trees to sample in a “clean” orchard is 21.  Sample 21 trees and record the number of fruit with live larvae in the 1st shaded column. (not # of larvae)  The 2nd shaded column is a running total of the number of CM infested fruit.  Compare that number to the number in the “Above” or “Below” columns to see if you need to continue.

Using the CM Control Worksheet Example 1. Percentage of fruit with live larvae is 1.3% and by the tenth tree sampled there is enough information to reject the orchard because it exceeds the 0.2% threshold for acceptance. - Begin recording data in the first line. - Compare the cumulative number to the “Above” and “Below” columns. - Here, the cumulative number at tree 10 matches the number in the “Above” column, rejecting the orchard as being too high risk.

Using the CM Control Worksheet Example 2. The percent infested is 0.0%, but can’t be determined until the minimum number of trees, 21, have been sampled. - Work same as previous example filling in count data. - With no larvae found a decision can’t be made until the “Below” column registers ‘0’. - At this point the orchard is accepted as being low risk.

Using the CM Control Worksheet Example 3. The final count is between 0.2% and 0.04% preventing a decision from being reached. -After reaching the last tree the count is 5 -Since 5 is between 3 and 8 an absolute decision can not be made. -At this point you either do another field sampling within 7 days or do a bin sampling. -If this happens again on second try, the orchard lot is rejected for export.

Questions?