This update will focus on Monilinia Blight
as we are in a critical time for blight risk in Nova Scotia!!!
Growing Degree
Days (GDD) Summary and Plant Development Updates
Figure
1. GDD Summary, May 16, 2023
Please find where you fit and plan accordingly.
Early fields in Nova Scotia
(Southshore counties and early fields/regions in Cumberland, such as Newville
Lake, Halfway River and Kirkhill):
·
Fields in those areas are in the early-flower
stage (before bloom, Figure 2)
·
This week should be the last week for
those fields to pass this year’s monilinia infection, but I would still be
cautious as you might need to put another blight spray on. Please check your
field and farm records.
·
For those areas/fields, I haven’t found
monilinia infection symptoms yet. I tried to find them but didn’t see anything
in the fields. We are probably having another lucky year in terms of monilinia
infection.
Figure
2. Wild blueberry early flower stage
Late fields and Cape Breton fields:
·
Those fields are very close to 40% F2 or
some might be past 40% F2 already. I probably won’t worry about the next two
day’s showers for those areas. I would pay attention to weather forecasts after
mid-week.
·
Those fields are still in a safe window to
apply pre-emergence herbicides, but the window is very narrow.
Central fields:
·
All areas/fields in central NS are at risk
for monilia infection. That’s why I said this is a critical time for NS fields
as the crop stages are in an ideal condition for blight infection and we are
going to get some showers here and there.
·
Remember, an application will provide 7-10
days of protection.
·
Most of the growers in those areas would
have applied first application around the weekend of May 6 so technically a
second application might be needed.
·
Some of the growers applied their first
application around the weekend of May 16, and this would give them a protection
window up to the Victoria Day weekend.
We are not out of the woods yet! Our crop fields are still
under the susceptible period (Figure 3)
Figure
3. Susceptible stages of wild blueberry to monilinia blight infection
The 5th and 6th
stems from left to right are where we are now.
Next update, May 19, Friday.
Hugh