10th Monilinia Update for Nova Scotia

Friday, May 25, 2018

With the exception of late ground in Cape Breton, the risk for new primary Monilinia infections has passed. If an infection has occurred over the last three weeks and the timing of the blight spray was off, you should be starting to see symptoms on the plants.

This is a picture from last year where you can see Monilinia infection on the flowers and the leaves.

We are rapidly moving into bloom, with many areas in central Nova Scotia at or above 20% open flower.  This is an ideal time to consider a first Botrytis spray, particularly if wet conditions are in the forecast. Not all fields in Nova Scotia have a history of significant Botrytis blight or other secondary crop year diseases like Septoria. However, you can find low levels of Botrytis in just about every field in Nova Scotia.  If weather conditions are wet and warm, it can lead to significant infections in any area of the province.

This will be the last Monilinia update for 2018, but I will continue to make updates for Botrytis Tuesday and Friday of next week and other updates throughout the summer.

9th Monilinia Update for Nova Scotia

Tuesday, May 22, 2018

Most fields in central Nova Scotia are beyond the risk of primary Monilinia infections at this point.

Any infections that have already occurred will start to show symptoms on the plants over the next week to three weeks depending on when controls were applied and when the infections occurred.

Cape Breton is still in the middle of infection risk as all sites reporting are beyond the 40-50% F2 threshold.

Skye Mt - 47% F2 (May 16th)
Borish - 77% F2 (May 18th)
MacLeod Settlement - 55% F2 (May 19th)
Keppoch - 50% F2 (May 20th)

These fields and other late fields that would have just reached this threshold within the last week and a half, would have experienced an infection period on Sunday.  The long warm wet period, combined with light frosts would have made the tissue susceptible to infection. The forecast is for more wet weather Wednesday, controls should be considered in these areas.

Many fields are starting to flower in central NS (Colchester, Cumberland and Pictou counties).  As fields approach early bloom controls for Botrytis should be considered, particularly in areas that are prone to this disease.

The next update will be late in the day on Friday May 25th.

8th Monilinia Update for Nova Scotia

Friday, May 18, 2018

Through the central part of Nova Scotia, we are rapidly approaching the end of the Monilinia season.  Flowers are starting to open and plants are popping through the ground in sprout fields.


Weather conditions have been very good this week for drying of apothecia cups. In many areas mature cups are drying up. Many fields in the central region do appear to be ahead of normal development.

However, fields that have just reached the 40-50% stage of development (within the last week) would still be susceptible for infection, particularly with the forecasted weather for the weekend. Mummy berries would still be producing cups and spores in late developing ground.

Growers should be starting to think about Botrytis controls and thinking about bringing in their pollinators in the next week or so.  Remember, always use caution and check with your beekeeper when spraying anything around bees. If you have to spray, spray in the evening to minimize contact with pollinators.

The risk for Botrytis is highest in coastal areas or areas that receive regular fog/wet periods. Weedy and denser canopy fields tend to be more susceptible to greater impacts from Botrytis infection. refer to the wild blueberry pest management guide for registered products http://www.perennia.ca/wp-content/uploads/2015/08/Wild-Blueberry-Pest-Guide-2018.pdf

Always check with your buyer to see what is allowable for their markets.

The next update will be late in the day on Tuesday, May 22nd.

7th Monilinia Update for Nova Scotia

Tuesday, May 15, 2018

Very few areas in Nova Scotia are not at the 40-50% F2/V2 stage.  High areas in Cape Breton are still not quite at threshold.

There is still infection risk for most sites in Nova Scotia, for Monilinia. We are still seeing mature cups, but given the dry windy weather we have been having, risk is starting to decrease especially in the early developing areas.

That being said, we are expecting an infection period Tuesday evening into Wednesday, depending where in the province you are located. Monitor your weather forecasts closely!

Above is the infection severity chart.  Wetness duration and temperature are the main factors to determine and infection period.  As temperature increases, wetness duration required for infection decreases.

As the season progresses, we start to see spore production reduce from the apothecia cups, however, as plants develop and floral buds and vegetative buds develop, they take longer to dry.

If a control product has not been applied and your buds are beyond the 40-50% F2/V2 stage, a control should be considered prior to the wet period or soon after.

The next update will be late in the day on Friday, May 18th.

6th Monilinia Update for Nova Scotia

Friday, May 11, 2018

We definitely had an infection period through much of the province last night, through this morning. Warmish temperatures and a long wet period certainly made for a high infection risk.

Most areas in main land Nova Scotia are now well above the 40-50% F2/V2 stage of development and would be susceptible to infection.  At many sites we are still seeing mature monilinia cups.

The current forecast is calling for a long dry period until the middle of next week. Which should further push plant development but will also help to dry up the cups and start to decrease infection risk.

Typically late developing fields (ie. Advocate area, Cape Breton and very eastern Nova Scotia) should be looking closely at their fields to determine if they have reached the 40-50% threshold.

I fully expect sprout fields in early developing areas (ie. Debert) to start having plants push through the ground by the first of next week.  Keep this in mind when considering herbicide applications.

The next update will be late in the afternoon on Tuesday, May 17th.

5th Monilinia Update for Nova Scotia

Tuesday, May 8, 2018

We had a series of infection periods over the weekend with the last being on Sunday evening into Monday morning.  We are currently in a stretch of warm dry weather which should push many areas beyond the 40-50% F2 V2 stage, if they are not there already. It looks like Thursday into Friday may be another wet period which many growers should be prepared for.

Reports from sites around the province:

South West Nova Scotia:
Queens - 90% F2
New Tusket - 81% F2
Annapolis - 69% F2

Murray Siding - 55% F2
Highland Village - 38% F2
Baseline Rd. - 45% F2
Eastmines - 44% F2
Mt. Thom - (tower field) - 26% F2

Debert - 77.7% F2

Kirkhill (by tower) - 75% F2

Westbrook/New Canaan - 77% F2

I don't have any reports from eastern Nova Scotia today, but fully expect bud development to be moving along rapidly.  All growers should be looking at fields for fruit bud development.

The next update will be Friday, May 13th in the late afternoon.

4th Monilinia Update for Nova Scotia

Friday, May 4, 2018

We certainly had infection periods over the last two days.  Growers only need to be concerned if their fields are at or above the 40-50% F2 V2 stage.   We are seeing rapid but variable bud development across the region.  The forecast for the next week is calling for variable weather but warmish temperatures.  I expect most fields in mainland NS will be approaching that critical stage by the middle of next week.  Only traditionally late areas, eastern NS and fields in higher elevation might still be delayed.

Note: in early developing areas we fully expect blueberry plants to start punching through the ground in sprout fields by the end of next week.

Also we are seeing apothecial cup development in multiple sites. So if buds are at the susceptible stage and weather conditions are right, it is likely that mummy berries are producing spores.

Site updates for May 4th

Western Musquodoboit valley - > 40% F2

Highland village - 4% F2
Baseline Rd. - 37% F2
Murray siding  - 30% F2
Kemptown - 7 % F2
Mt. Thom - 4 % F2
Camden - 40% F2

Debert - 50% F2

Oxford - 30% F2 (3 pins, 4 nearly mature and 4 mature)

Lynn Mt. - 14% F2

Amherst - 15% F2 (2 pin and 3 nearly mature cups)

Westchester - 19% F2 (4 pin)

The next update will be late in the afternoon on May 10th.