G.L. Graham and M.J. Melanson
Partner: Bleuets NB Blueberries
Abstract: Mosses, in particular hair-cap moss (Polytrichum commune), are difficult to manage
within wild blueberry production. The change in management practices towards less burning as a pruning method
has increased moss prevalence, as regular burning can decrease moss populations. In the spring of 2009, a trial
was established near Pennfield, New Brunswick in a commercial wild blueberry field entering the vegetative phase
of production. The highest rate of flumioxazin suppressed blueberry growth, but not at a commercially significant
level. Flumioxazin at 214 g ai/ha or 143 g ai/ha plus NIS also caused slight injury, although plants recovered by
the end of the sprout year with no significant injury in the crop year. Hexazinone had no effect on hair-cap moss.
A rate effect was present for flumioxazin over all rating dates, with improved control at higher use rates. For
season-long control, either a rate of 428 g ai/ha flumioxazin or 143 g ai/ha plus NIS would be required. The lower
use rate with NIS has a lower application cost and potentially could improve crop safety. Control levels declined
early in the crop year, indicating that multiple applications or different application timings may be required
for moss control.