Enhancement of phenoxy effects by addition of Assist. Guggenmoos, S.
Stem kill was previously reported in this trial where Assist oil concentrate was added to a commercial application of diphenoprop intended to control 2 metre regrowth of tall growing tree species on a power line right of way in the Judy Creek oilfield, Alberta. Application occurred between August 12 and 14, 1987 using a hose and gun from both aerial bucket and soft track machines. Assist, at 0.5% v/v, was added to a mix of 350 g 2,4-D plus 350 g 2,4-DP per 1000 L solution. Brush was sprayed to the point of run-off with an average volume of 1885 L/ha. Stem kill, sprouts and sprout length were evaluated for poplar species on October 25, 1989. These results are compared with the standard treatment of 350 g 2,4-D plus 350 g 2,4-DP per 1000 L solution sprayed to run-off. Data for the standard is derived from previous trials.
Comparison of diphenoprop vs diphenoprop + Assist for brush control
| MEAN STEM KILL | SPROUT FACTOR2 | ||||
| TREATMENT | a.i./1000 L | Trembling aspen | Balsam poplar | Trembling aspen | Balsam poplar |
| 2,4-D + 2,4-DP | 350g + 350g | 9 b1 | 4 a | 118 b1 | 20 a |
| 2,4-D + 2,4-DP + Assist | 350g + 350g + 0 .5% | 9 b | 9 b | 107 b | 18 a |
1Duncan’s Multiple Range Test at 5% level
2number of sprouts X maximum sprout length
Stem kill for balsam poplar was significantly increased by the addition of Assist at 0.5%
v/v. No significant reduction in sprout formation and growth, as indicated by the sprout factor,
was observed. (TransAlta Utilities, Sherwood Park, Alberta)