Another update before the weekend.
Wild Blueberry Floral
Bud F2 Stage and Monilinia Infection Periods
As I mentioned in the last update on Tuesday, May 3, a
lot of fields in the central area are at or beyond 40% F2 and by looking at
weather stations installed in wild blueberry fields, starting Wednesday evening
(May 4) to Thursday morning (May 5), there could be a moderate to high
infection period during this time.
It looks like we will have a warmish and dry week next
week according to the information from Environment Canada and those stations we
have in wild blueberry fields (see Table 2.). You might be able to drag the
first monilinia application to a further time before the next wet weather is
forecasted.
It is a little bit early to talk about when to stop
worrying about monilinia blight infection and treatment application, but I want
to put this information out early. This graph shows what are some susceptible
stages/periods for spores to infect blueberry buds/leaves.
We do not have a threshold for when we should stop
monilinia blight application, but a good way to look at this question is when
the crop has reached the stage where the leaves have unrolled or the first
blossoms are visible the susceptible period is past and sprays are not
required.
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 1. 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)
*Once the areas and
fields get to 40% F2 or above, I will stop updating numbers as I can focus on
other areas. Once you are at or above 40%, please monitor your local weather
and make a management decision.
|
Wild blueberry production regions, NS |
The average percentage of floral buds at
F2 |
|
|
|
|
Cape Breton |
|
|
|
|
|
Cumberland County |
|
|
Oxford (early field) |
May 5- 46% |
|
Mapleton (Lynn Mt.) |
May 5- 49% |
|
Halfway River |
April 26- 40% |
|
Lower Greenville |
April
25- 15% |
|
Westchester Station |
April
25- 17% |
|
Fenwick |
May 2- 40% |
|
Springhill |
May 3- 41.2% |
|
Diligent River flat |
May
5- 10-15% |
|
Wentworth |
May 2- 40% |
|
New Canaan |
May 5- 40% |
|
Millvale |
May
3- 34.7% |
|
Windham Hill |
May 3- 13.8% |
|
Prospect and Newville Rd. area |
May 5- 30-35% |
|
York Settlement/ Glasgow Mt. |
May 5- 30-35% |
|
Fox Point |
May 5- 20% |
|
|
|
|
South West Nova Scotia |
|
|
Queens County |
April 23- 42% |
|
Digby County |
April 29- 50% |
|
Annapolis County |
April 29- 50% |
|
|
|
|
Hants County |
|
|
|
|
|
Halifax County |
|
|
|
|
|
Guysborough County |
|
|
|
|
|
Colchester County |
|
|
Murray Siding |
May 5- 72% |
|
Belmont |
May 5-
35% |
|
Glenholme |
May 5- 49% |
|
Debert (WBPANS office) |
May 2- 44% |
|
Debert (Debert Airport) |
May 2- 45% |
|
Debert (near the railway track) |
May 2- 40% |
|
Baseline Rd. |
May 2- above 40% |
|
Greenfield |
May 6- 50% |
|
Economy |
May 2- 40% |
|
Portapique |
May 2- 40% |
|
Highland Village |
May 2- 27% |
|
Great Village |
May 2- 27% |
|
Tatamagouche Mt. |
May 2- 17% |
|
|
|
|
Pictou and Antigonish County |
|
|
New France |
April 27- 5% |
|
Maryvale |
April 27- 5% |
|
Mt Thom |
April 27- 12% |
|
Kemptown |
April 27- 15% |
|
Sunny Brae |
April 28- 5% |
*Thanks to everyone who
contributed information and a special thank you to staff from the Bragg group
(Roy Hunter and Richard Langille) who share information with me weekly.
Table 2. Weather Forecast for
Potential Wetness and Monilinia Infection Periods
|
Weather
Station and Location |
Potential
Wetness and Monilinia Infection Periods *ONLY
when your field is at or above 40%!!! *Predict
period: May 7-12; reported date: May 6 |
|
Colchester |
|
|
Glenholme
(NSW001) |
No |
|
Murray
Siding (NSW002) |
No |
|
Upper
Kemptown (NSW022) |
No |
|
Kavanaugh
Mills (NSW023) |
No |
|
Debert
(NSW036) |
No |
|
Belmont
(NSW037) |
No |
|
Staples
Brook (NSW038) |
No |
|
|
|
|
Cumberland |
|
|
Wyvern
(NSW003) |
No |
|
Oxford
(NSW005) |
No |
|
Halfway
River (NSW039) |
No |
|
|
|
|
Pictou |
|
|
Blue
Mountain (NSW017) |
No |
|
Sunny Brae
(NSW018) |
No |
|
New
Gairloch (NSW019) |
No |
|
Keble
(NSW020) |
No |
|
Four Mile
Brook (NSW021) |
No |
|
College
Grant (NSW040) |
No |
|
|
|
*Weather source: weather stations in wild blueberry fields (http://www.novascotiawildblueberryblog.com/p/weather.html)
Sprout Field Development and Observation
According
to the wild blueberry sprout year GDD development model (Plant emergence starts
at 270 GDD), we are not there yet. However, with this warm weather, it is
expected to see sprout field plants start emergence by the end of next week.
From my observation in sprout fields, I haven’t seen plant emergence occurring
yet.
According
to a report and observation from the researcher, it was noticed that a lot of
shoots sprouting from the base of cut stems and those fields with partially cut
stems have formed a lot of buds at the base (see photo below). This would be
something for you to watch for if you are going to apply your spring
herbicides.
Photo
credit: Scott White