Wild Blueberry Newsletter, August 2016

Wild Blueberry Newsletter header graphic, text and a photo of blueberries and leaves

August 2016

Wild Blueberry Crop Prospects 2016

The 2015 Maine wild blueberry crop was 101.11 million pounds, less than the 104 million pounds in 2014 but more than the 5-year average of 93.4 million pounds.  The total wild crop for 2016 is estimated to be at 300 million pounds, 20 million pounds less than 2015. The cultivated crop is estimated to be at 740 million pounds, down 10 million pounds from 2015.


– David Yarborough, University of Maine

The blueberry plants in Maine had a long fall and an extremely warm winter with little snow cover that melted early, so there was little frost in the ground.  We did not observe any winter injury, which was expected with the mild conditions. There were only a few scattered frosts, so very little damage occurred from this.  There were widespread reports of a new type of injury seen in wild blueberry fields this spring.  The plants had stopped developing or had not developed at all in some fields, especially in the low areas of many fields, cold air flows like water and will accumulate in the low spots in fields.  We believe the injury was caused by the very warm weather we had in early April followed by 11 to 18°F temperatures recorded on April 28-30.  Normally wild blueberries would not be injured by these temperatures before bloom but with the early warm temperatures the plants lost their winter hardiness and with the lack of frost the groundwater began to move back into the tissues.  The cold temperatures then froze the water and disrupted the tissues. This injury was spotty and did not occur in all fields but we can expect an overall reduction of the crop by about 15%.  We had a large bloom in areas not affected by the injury so there were plenty of blossoms, providing the potential for a large crop.  The mid-coast Union area had excellent weather conditions and an exceptionally high fruit set. The Downeast fields also had good pollination weather as well. We had a fairly dry spring and had few infection periods for mummy berry disease. Tony Jadzack’s estimate for bees contracted to pollinate wild blueberries was 58,833 hives, which is considerably less than last year’s 77,000 hives.  In Jonesboro, we received 2.5, 2.7, 2.8 and 3.04 inches of rain in April, May and June, and July respectively. Despite the dry spring with the yearly rainfall being below normal, cool temperatures provided for both good blueberry and weed growth.  Crop progress is a bit delayed Downeast but could catch up with warmer temperatures and more rain.  If we continue to get adequate moisture for the remainder of the summer, the crop in Maine could be about average at 100 million pounds.


– Pierre-Olivier Martel, Quebec Agriculture Ministry

In Quebec, we had a mild winter with good snow cover on the entire wild blueberry production area, so we didn’t notice any winter damage. This spring, we had a nice bloom without frost injury to the flowers.  The weather was not favorable to mummy berry infection and there was little flea beetle seen.  The bloom period was not ideal as the cold and rain probably reduced pollination, but fruit set seems to be good.  Since May, we have had plenty of rain so drought isn’t a problem in most of the production areas.  If the yields are consistent overall, we expect the crop to be greater than average with more than 70 million pounds.

Nova Scotia

– Peter Burgess, Perennia

Nova Scotia had a relatively mild winter with snow leaving blueberry fields early.  Development started early but unusually cool and dry conditions in April and May slowed blueberry development.  By early May, crop development was essentially in line with a normal year throughout the province.  Some winter damage was evident, but it was relatively minor.   There were several frost level events through late April.  Most of these were not significant but it looks like some fields suffered more than others, particularly in low lying areas. We appeared to have a more normal year for Monilinia infections, compared to the last two (which were dry), with several infections periods. However, damage to Monilinia was low. June was damp and cool with some Botrytis pressure noted.   There were two separate frost events in mid-bloom with some effect on the crop. Nova Scotia again brought in 4000+ hives from Ontario through the import permit program.  Domestically Nova Scotia had low winter honey bee losses, and over 24,000 of those hives were used for pollination.  The use of Bumble bee quads is continuing to increase as well. There were lots of native pollinators again throughout the province, but we are seeing a slight decrease in numbers. The weather during bloom was not ideal but there were adequate flying days to allow for pollination, in western and central Nova Scotia. The eastern part of the province was more challenged by weather during bloom.  Dry conditions have persisted through late June and into July so rain over the next two weeks will be critical. That being said many are still encouraged by the crop they are seeing and we are still expecting a very good crop, well into the 50 million pound range.

New Brunswick

– Michel Melanson, NB Department of Agriculture, Aquaculture and Fisheries

A mild winter in New Brunswick resulted in minimal winter injury.  The fields developed early in spring with the warm weather in early April.  Some of the field had early fruit bud swelling, but in mid-April, the cold weather returned, and some localized spring injury was observed.  The developmental stage of the fruit buds were in the normal time after cool weather.  A few Monilinia blight infection periods occurred, but most growers had good timing and coverage with only a few localized disease plants.  A wet and cool period persisted during bloom, affecting pollination.  Some botrytis blight was observed.  Some localized frost also occurred during bloom.  Although bloom weather was not ideal, fruit set seems to be good, with enough good days for bees to visit flowers. More than 35,000 honey bee colonies were used for pollination in wild blueberry fields, similar to previous years.  The use of bumble bees is increasing while the number of Alfalfa leafcutter bees seems to have levelled.  The very early fields have some ripe fruit, but the crop development is similar to previous years.  With good rainfall over the next few weeks and warm temperatures, the crop in New Brunswick should be average to the previous couple of years.  It is expected that the crop will be slightly greater than the 51.2 million pounds.

Prince Edward Island

– Chris Jordan, PEI Department of Agriculture and Fisheries

Prince Edward Island had a very mild winter and substantially less snow cover compared to the previous year. Very little winter injury resulted. Crop development was more uniform across regions of the province which presented a challenge for growers managing large acreages to protect their crop from Monilinia in a timely manner. There appeared to be larger variation within fields compared to normal. A few spots did show symptoms of Monilinia, but relatively low incidence overall despite several infection periods which did occur.  There was significant variation in pollination weather during the month of June. Early fields and late fields had good flying days overall. However, mid-June brought with it two weeks of solid rain and cold weather, with scattered hours of acceptable flying time for honey bees. The increasing use of bumblebee quads used in conjunction with honey bees helped to offset the poor weather during mid-June. This appeared to be a good strategy for obtaining adequate pollination. The estimated 7,000 resident PEI honey bee colonies were supplemented with approximately 4,800 imported colonies from Ontario. Botrytis blight has proven to be a challenge and some yield reduction due to infections is possible. Hard frosts hit during late May and mid-June with only slight damage sustained to blossoms. Late June and early July has been very dry and despite the challenging weather patterns, fruit set appears good up to July 8, 2016. PEI is expecting an above average (more than 22 million pounds) crop in 2016.

Five-year wild blueberry yields for Maine and the Canadian Provinces, 2016 bar graph

Letter from Anthony Jadczak

Please read the attached letter (PDF), above, from Tony Jadczak. Tony has been a great asset and tireless worker for the wild blueberry industry, he will be missed and we wish him the best of luck in his new career.


David E. Yarborough
Extension Blueberry Specialist

Wild blueberry fact sheets, past newsletters, contacts, resource links, calendar of events, and more can be found on the Cooperative Extension’s Maine Wild Blueberries website.

Information in this publication is provided purely for educational purposes. No responsibility is assumed for any problems associated with the use of products or services mentioned. No endorsement of products or companies is intended, nor is criticism of unnamed products or companies implied.

© 2016

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