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
Trembling
Balsam Trembling
Balsam
TREATMENT
a.i./1000
L
aspen
poplar aspen
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)