Edward Kettela and Peter Silk
Natural Resources Canada, CFS-AFC

SERG Project #2000/06
Year of Project: 2004
Report Received: 2005

A mating disruption trial using aerially applied Hercon Disrupt Microflakes containing synthetic sex pheromone of the spruce budworm (Choristoneura fumiferana (Clem.)) was successfully carried out in 2004 at Balsam Lake Provincial Park, Ontario, on 30-year-old plantation white spruce. Treated and untreated sites were compared. Feral spruce budworm populations were moderate to high in the park and surrounding region. The population in the park was essentially isolated and re-invasion was negligible. The entire plantation area, except the control site, was treated with product: 46 ha were treated at 50 g/ha and the remaining 20 ha at 15 g/ha. Product was applied close to the first male trap capture and the onset of mating.

Excellent deposit of the flakes was achieved throughout the blocks using a Cessna 188 and open nozzles, with deposit being about three times higher in the 50 g/ha block than in the 15 g/ha block.

The half-life of the 1 x 3 mm Hercon flake containing the spruce budworm pheromone was determined to be about 14 days.

Trap capture of male spruce budworm moths in baited Multipher traps dropped to zero 24 hours post-treatment, indicating pheromone presence throughout the test period.

Egg masses were deposited in all sites, but egg mass accumulation was very flat in the 50 g/ha block, 1.16 per branch on 24 June to 1.32 on 12 July, compared to 3.98 to 13.20 in the 15 g/ha block.

In mating cages, 94% of the feral female moths in the 50 g/ha block were unmated, as well as 52% in the 15 g/ha block and 18% in the untreated site. In the 50 g/ha block, mating suppression was uniform over the sample period (94.4% to 88.8% on the last sample).