control the weed as effectively when
evaluated at seven weeks after application.
Although Milestone caused the majority of
plants to wilt and die, new plant growth
was observed after application but at
levels much lower than the other tested
herbicides. Digging up tansy ragwort and
removing all the roots was also effective
and no regrowth occurred throughout the
season. Although digging up plants would
be an effective way to deal with very small
patches of tansy ragwort, larger infestations
may be more efficiently controlled with a
herbicide like Milestone. This experiment
will be duplicated in 2016.
TABLE 1. Summary of different management options to control tansy ragwort**.
Management
Strategy
Rate Effectiveness
(% visual control)
2 weeks*
7 weeks*
Milestone
Restore II
2,4-D Amine 600
Banvel II
Mechanical Control
(digging)
152 mL/ac
850 mL/ac
1.6 L/ac
1 L/ac
Roughly 30-60
seconds per plant
80%
80%
50%
30%
100%
100%
80%
40%
30%
10%
100%
100%
* After application.
** Plant density was around 1,000 per acre.
FIGURE 3. A flowering tansy ragwort plant during August.
Kate Ayers
is from the University of Guelph, Ontario
Agriculture College.
Mike Co