Hi, everyone. Here is the mid-week update. The weather is looking good for the next few days across the province. We are expecting to see double-digit air temperatures continuously. We are observing field/natural signs of plant development and growth acceleration, such as the emergence of lily of the valley, bunchberries, green grasses, as well as blueberry sprout field bud development.
The next possibly concerning wet periods for growers
in the early areas of central NS is from mid to late next week (Monilinia
blight spray).
NS Cumulative
Precipitation
Source:
Jeff Franklin (AAFC Kentville) and Michelle Cortens (Tree Fruit Specialist,
Perennia, Orchard
Outlook Newsletter Vol. 24 NO 2.). Figure 1 is a graph of cumulative
precipitation over the last five years including rainfall and the rainfall
equivalent from snow. Rainfall contributed to most of this year's cumulative
precipitation. Jeff Franklin shares that, "The cumulative precipitation
plot shows that we are currently above the 10-year trend and that most of our
precipitation has come in March and early April with some significant single
day rainfall events. It also shows data from 2019, when we received our
precipitation in smaller more frequent events. The data from 2019 shows that we
had rain on 40 days in the months of April and May!"
Figure 1: Both rainfall and the rainfall equivalent
from snow at the Kentville Research Station from 2019 to 2024. Provided by Jeff
Franklin (AAFC).
Growing Degree
Days (GDD) Summary and 2024 Spring Plant Development Prediction
This year, we are going to report GDDs from 17
stations (see Figure 2) which cover the major wild blueberry production regions
in NS. There are different ways to obtain GDDs by choosing the station you
like. To learn how to obtain GDDs, please read this blog post: http://www.novascotiawildblueberryblog.com/2023/04/2023-wild-blueberry-pest-guide-new.html.
Figure
2. 17 Wild Blueberry Stations for GDD updates
Here is a summary of the most up-to-date GDD from 17 weather
stations in wild blueberry fields.
Figure
3. GDD Summary, April 22, 2024
Plant Development and Management Recommendations for the
Next 7 Days
Sprout fields:
If the weather station you follow reaches above 90 GDD as of April 22, I would recommend growers use the dry window for the next few days to spray pre-emergence herbicides (Chikara, Ignite, Spartan/Involve 50 WDG, Velpar and their tank mixing). The next wet/rain is looking around mid-week for the most of central early growers. It is also good to spray herbicides a few days before the forecasted rain as wet soil improves those chemicals’ efficacy, especially Chikara and Ignite.
If the weather station
you follow is still below 80 GDD, after this warm and dry week, you would be
looking around the first few days in early May to spray pre-emergence herbicides
in your sprout fields.
Crop fields:
Fields in the Southshore areas, West Advocate and Halfway River (near Parrsboro) are in the early to mid stages of monilinia infection. Growers in the above-mentioned areas should monitor field and weather conditions closely for the next few days. The first monilinia blight spray might be needed very soon.
Other areas are still early for monilinia blight infection.
Here is another piece of information I want to share from the Highbush Blueberry Monilinia Blight Management network by Sonny Murray (Berry Specialist, Perennia, Monilinia Blight Forecast Post #1 April 22nd.)
Newly emerged apothecia
(the structure produces disease spores) have been observed in the Waterville
and Aylesford areas (Annapolis Valley). Please note, that this is just a piece
of additional information to help us determine this season’s monilinia blight
infection window in wild blueberries. Normally,
the central wild blueberry fields are about 2-3 weeks behind the Annapolis
Valley’s highbush blueberry development in the spring. This is also a warning
sign that this spring condition is favourable for monilinia blight apothecia
development, given the wetness and warmness we have.
Figure 4. Highbush Mummy Berries Apothecia, from Sonny Murray
Wild Blueberry Floral
Bud F2 Stage
Please see the below summary table of the percentage of
wild blueberry floral bud at the F2 stage. You can also click on this map to
check those numbers. Detailed information is also available under the Wild
Blueberry Blog- GDD&
Phenology Tracker.
Table 2. Percentage of Wild Blueberry Floral Bud F2
stage
light green (0-20% F2), dark green (20-30% F2), yellow
(30-40% F2) and red (40-100% F2)
|
Wild blueberry production regions, NS |
The average percentage of floral buds at
F2 |
|
|
|
|
South West Nova Scotia |
|
|
Queens County |
>40%- April 24 |
|
|
|
|
Hants County |
10%- April 19 |
|
|
|
|
Cumberland County |
|
|
West Advocate |
20% F2- April 19 |
|
Kikhill |
10-15% F2- April 19 |
|
Halfway River |
30-40% F2- April 19 |
|
|
|
|
Colchester County |
|
|
Belmont |
9% F2- April 23 |
|
Murray Siding |
20% F2- April
23 |
|
Camden |
13% F2- April 23 |
|
|
|
|
Halifax Regional Municipality |
|
|
Middle Musquodoboit |
10%- April 23 |
|
Dean |
5%- April 23 |
|
|
|
|
Guysborough County |
0% F2- April 19 |
|
|
|
|
Pictou and Antigonish County |
0% F2- April 19 |
|
|
|
|
Cape Breton |
0% F2- April 19 |