Frost Damage in Saskatoon Bushes

POSTED IN For Growers ON 5/19/2016

Well, we had quite a chiller go through this past weekend, and some have seen frost damage. While saskatoon bushes are pretty harder throughout the winter, they are a bit more suseptable when they are in blossom. In Northern Michigan they have seen some signs of damage, though not as threatening as with some other crops.

Elsner_Duke_2013_CroppedDr. Erwin ‘Duke” Elsner, Small Fruit Educator with Michigan State University Extension recently helped us understand how to tell if your plant has frost damage, and what to do about it:

Frosted tender leaves will show darkened margins, almost black in color.  The injured tissue doesn’t grow or stretch as the rest of the leaf continues to grow, so the leaves look more crooked or crumpled the season continues.

Lightly frosted flowers just show some browning of the petals.  

Nothing needs to be done to these light frost injured plants. Under most circumstance they will continue to grow and produce this season.

Best wishes to all you growers and harvesters this season.  If you find that you have unusual damage due to cold temperatures, please let us know.

 

Saskatoon Sawfly & Saskatoon Bud Moth

POSTED IN For Growers ON 5/19/2016

 First Documentation of Saskatoon Sawfly in Michigan – May 13, 2016 

Late last week I observed saskatoon sawfly (Hoplocampa montanicola) for the first time in Michigan, at the Northwest Michigan Horticultural Research Center in Leelanau County. I had suspected that some fruit injury seen at this site in 2015 was due to this insect, and growers had previously reported injury of a similar nature, but this was the first time the insects have actually been found. 

saskatoon sawflyAdult saskatoon sawfly 

Adults of the saskatoon sawfly were plentiful (more than ten on a bush at some times) and very actively flying amongst the flower clusters (plants were at approximately 50% bloom at the time). Although I observed the sawflies for some time, I was not able to actually see one attempt to lay eggs. Based on what I have gathered from Canadian references, the egg laying behavior might not start until the flower ovaries start to swell after fruit set. Good pictures of the egg laying scars, larva and fruit damage can be seen at http://www.prairie-elements.ca/saskatoon/11.2-insects1.pdf. The potential threat for fruit losses in Michigan has not been determined, but this pest is an important one in Alberta and Manitoba. 

Saskatoon sawfly is not listed in the 2016 Saskatoon Berry Pesticide Recommendations that I released earlier this spring. Based on recommendations made for a related pest of apples in Ontario, sprays of Assail, Altacor or Exirel at petal fall would be the best choice. These are all toxic to bees, so it is important that all bee activity be completed before the application. 

Larvae of Saskatoon Bud Moth Now Active 

On the same date and location I also noted the first larvae of saskatoon bud moth (Epinotia bicordana) for the season. Small larvae, a little over 0.25 inches in length, were feeding inside nests of tender leaves they had webbed together with silk. They must have been active here much earlier, as their first feeding of the year occurs as they bore into the bases of swelling buds. They were not numerous, so the early feeding on buds would likely have been very hard to detect. According to Canadian literature, the development and feeding of the larvae is 

completed by the time of petal fall; the early season feeding inside buds is the damaging time as it can kill entire buds or injure some of the flowers. The later feeding on leaves is of no consequence to production. The importance of saskatoon bud moth to production in Michigan is uncertain. It is too late this year for sprays to reduce bud injury or fruit loss. 

Curled leaves from saskatoon bud mothSaskatoon Bud Moth

 

 

 

 

 

 

 

 

 

 

Leaves tied together by saskatoon bud moth larvae (left), and close up of a larva (right). 

 

 

 

Duke Elsner, Small Fruit Educator, Michigan State University Extension elsner@msu.edu 

Saskatoon Growers Education Tour 2016

POSTED IN For Growers ON 5/16/2016

SASKATOON GROWERS EDUCATION TOUR

JUNE 17, 2016

Saskatoon Growers Education TourThe day’s agenda is as follows (for mapping information, click on any location shown below):

 

8:15 AM        MEET AT JACOB’S FARM, M-72 WEST

                        (Coffee and Saskatoon muffins)

                        (RESOURCE PERSON: DR ERWIN DUKE ELSNER)

  • PRUNING METHODS
  • PESTS
  • CARING FOR OLDER PLANTS
  • COMPARING VARIETIES

 

10:00 AM      MEET AT JIM DIXON’S FARM, ACME

                        (RESOURCE PERSON: JIM DIXON)

  • CARE OF YOUNG BEARING PLANTS
  • COMPARING VARIETIES
  • FUTURE MARKETING OPPORTUNITIES

 

11:00 AM      MEET AT DUCHENEY’S NEW PLANTING

                        (RESOURCE PERSON: STEVE DUCHENEY)

  • TIPS ON PLANTING NEW STOCK
  • CARING FOR YOUNG PLANTS
  • OUTLOOK FOR PLANTING STOCK
  • IMPACT OF MULCHING

 

12:30 PM      MEET FOR LUNCH TO SHARE WITH OTHERS