HV Blend for Protection against Ips typographus three-component 22564524 blend of 1-hexanol, -hexen-1-ol, and hexen-1-ol, previously deployed by Zhang & 1692608 Schlyter. A pheromone only trap and a blank trap were included as controls. Six treatments with anti-attractants were tested: the first treatment included the pheromone and the anti-attractant verbenone . The second treatment had pheromone plus 1-hexanol and verbenone as anti-attractants. This treatment was included to test if tC could be replaced by -verbenone and a ten times higher release rate of 1-hexanol than previously used. In three of the treatments, pheromone plus -verbenone and 1-hexanol were tested in combination with three release rates of tC. Finally, a sixth treatment was a positive control that was the previously tested three-component GLV blend at its original release rates combined with tC and verbenone. Two sets of the eight differently baited traps were placed in two rows. One set consisted of pipe traps and the other of Lindgren multiple-funnel traps. The minimum distance was 10 m between traps and 25 m between traps and the forest order DCC 2618 border. Baits in pipe traps were rotated 13 times, whereas baits in Lindgren traps were rotated 8 times before flight activity ceased. Trial 2: 
The experiment in 2007 was performed from 15 May to 19 July in Germundslycke in South East Sweden in a privately owned area cleared from trees after a heavy bark beetle outbreak the previous year. Permission for the experiment was granted by the owner. In this test, we primarily aimed to investigate the inhibitory effect on trap catch of pure tC compared to that of T-tC. Two lines with pipe traps were placed with.10 m between traps and one line with Lindgren multiple-funnel traps was placed perpendicular to the two other lines. Each line consisted of nine traps including seven treatments with anti-attractants, a blank control trap, and a trap baited with only pheromone as a second control. The first treatment included pheromone and verbenone. The second had pheromone plus -verbenone and 1-hexanol as anti-attractants. The third treatment had the same compounds as the second treatment, but a ten times higher release of 1-hexanol. The forth and fifth treatments included 0.05 mg/day or 0.5 mg/day of pure tC, respectively, in addition to 1-hexanol and -verbenone. The sixth treatment included T-tC instead of tC, but was otherwise identical to treatment five. Finally, the seventh treatment had a ten times higher release rate of T-tC to test whether a contingently lower efficiency of T-tC could be compensated for by a higher release rate. The lowest tested release rate of tC and the ten times higher rate of 1-hexanol without tC were included here to verify the results from Trial 1 at higher beetle population levels. All baits in a line were tested three times at each position in that line, resulting in a total of 27 replicates for each line and a grand total of 81 replicates for the three lines together. Trial 3: The experiments in 2008 were performed during May in Parismala, Southeast Sweden in a privately owned forest. Permission for the experiment was granted by the owner. The regional bark beetle population density was high following two years of numerous mass attacks. To study whether DHC had inhibitory effects on pheromone trap catch, we used one row with four pheromone-baited pipe traps separated by at least 10 m. Traps were baited in the following way: a pheromone alone control; 4 NHV Blend for Protection aHV Blend for Protection against Ips typographus three-component blend of 1-hexanol, -hexen-1-ol, and hexen-1-ol, previously deployed by Zhang & Schlyter. A pheromone only trap and a blank trap were included as controls. Six treatments with anti-attractants were tested: the first treatment included the pheromone and the anti-attractant verbenone . The second treatment had pheromone plus 1-hexanol and verbenone as anti-attractants. This treatment was included to test if tC could be replaced by -verbenone and a ten times higher release rate of 1-hexanol than previously used. In three of the treatments, pheromone plus -verbenone and 1-hexanol were tested in combination with three release rates of tC. Finally, a sixth treatment was a positive control that was the previously tested three-component GLV blend at its original release rates combined with tC and verbenone. Two sets of the eight differently baited traps were placed in two rows. One set consisted of pipe traps and the other of Lindgren multiple-funnel traps. The minimum distance was 10 m between traps and 25 m between traps and the forest border. Baits in pipe traps were rotated 13 times, whereas baits in Lindgren traps were rotated 8 times before flight activity ceased. Trial 2: The experiment in 2007 was performed from 15 May to 19 July in Germundslycke in South East Sweden in a privately owned area cleared from trees after a heavy bark beetle outbreak the previous year. Permission for the experiment was granted by the owner. In this test, we primarily aimed to investigate the inhibitory effect on trap catch of pure tC compared to that of T-tC. Two lines with pipe traps were placed with.10 m between traps and one line with Lindgren multiple-funnel traps was placed perpendicular to the two other lines. Each line consisted of nine traps including seven treatments with anti-attractants, a blank control trap, and a trap baited with only pheromone as a second control. The first treatment included pheromone and verbenone. The second had pheromone plus -verbenone and 1-hexanol as anti-attractants. The third treatment had the same compounds as the second treatment, but a ten times higher release of 1-hexanol. The forth and fifth treatments included 0.05 mg/day or 0.5 mg/day of pure tC, respectively, in addition to 1-hexanol and -verbenone. The sixth treatment included T-tC instead of tC, but was otherwise identical to treatment five. Finally, the seventh treatment had a ten 23143416 times higher release rate of T-tC to test whether a contingently lower efficiency of T-tC could be compensated for by a higher release rate. The lowest tested release rate of tC and the ten times higher rate of 1-hexanol without tC were included here to verify the results from Trial 1 at higher beetle population levels. All baits in a line were tested three times at each position in that line, resulting in a total of 27 replicates for each line and a grand total of 81 replicates for the three lines together. Trial 3: The experiments in 2008 were performed during May in Parismala, Southeast Sweden in a privately owned forest. Permission for the experiment was granted by the owner. The regional bark beetle population density was high following two years of numerous mass attacks. To study whether DHC had inhibitory effects on pheromone trap catch, we used one row with four pheromone-baited pipe traps separated by at least 10 m. Traps were baited in the following way: a pheromone alone control; 4 NHV 11578659 Blend for Protection a