Midsummer vineyard management; veraison management workshop August 6

By Terence Bradshaw

We will host a veraison / preharvest vineyard management workshop at the UVM Horticulture Research & Education Center on August 6th, 3:00 – 4:30. This is folded into a larger Research Open House, I sent a flyer in a previous email (also available at: http://go.uvm.edu/hrecresearchday). We will cover out latest research on cold-climate grape cultivars, management decisions to be made as veraison approaches, and preharvest juice sampling to time harvest. There is no charge for this event, just show up. The rain date will be August 9, watch this email list for word if we do move it.

Most spraying in Vermont vineyards should be wrapping up as the vines and especially fruit are becoming resistant to most diseases. However, if you have downy and powdery mildew in the vineyard, it would be wise to maintain protection against them through veraison. Vines which have not reached bunch closure may also be protected against botrytis for one last time before veraison and harvest.

Japanese beetles are probably in every vineyard in the state. Their damage can generally be tolerated on established vines, but vines under 3-4 years old should be protected. Grape berry moth are mostly in pupal stages in Champlain Valley vineyards, although in some inland/cooler areas larvae may still be feeding. Careful and thorough scouting for webbing between berries will determine the presence of the pest. The threshold for treatment against the current generation is 6% of clusters with signs of damage.

Canopy management is critical at this time of the year- every fruit cluster should see at least some direct sun. However, if opening up congested vines at this time, be careful not to fully expose clusters that have been heavily shaded, as the risk for sunburn increases when a shaded cluster is exposed to full sunlight in midsummer.

Get your bird netting ready.

Where trade names or commercial products are used for identification,

no discrimination is intended and no endorsement is implied.

Always read the label before using any pesticide.

The label is the legal document for the product use.

Disregard any information in this message if it is in conflict with the

label.

The UVM Tree Fruit and Viticulture Program is supported by the

University of Vermont Agriculture Experiment Station, a USDA NIFA E-IPM

Grant, and USDA Risk Management Agency Funds.

Midsummer orchard management

By Terence Bradshaw

High summer is here, the time that apple growers can relax (a little), maybe go away for a few days, and just get ready for money to fall off the trees. While that’s a bit of an exaggeration, this has always been one of my favorite times in the apple season, as we watch the fruit size up with a lot less work than earlier in the season.

Pest management: thinks are pretty simple now. Insects drive your fungicide sprays, as there is room to stretch the latter out on a 2-3 week schedule depending on rain. If you still have active scab in the orchard, captan every 10-14 days is still on the menu, but leaves and fruit are becoming more resistant to new infections, and existing lesions should be burning out. Sooty botch. Fly speck, and fruit rots should be the main targets, select your material of choice based on the New England Tree Fruit Management Guide.

As for insects, that really depends on things farm by farm. Some orchards have already seen sufficient trap captures to trigger an apple maggot fly spray, check your traps and be ready to treat when average trap captures hit one per block for non-baited traps or five for baited traps.

Second generation codling moth are just flying now, so egg hatch is still a few weeks away. Obliquebanded leafroller, if they are a problem in your orchard, could be treated any time now but I’d plan on scheduling that with your maggot spray.

Every spray tank should include some calcium product at this time of year. For Honeycrisp and Cortland especially, you may need to make some passes with just calcium to keep bitter pit at bay.

Now through mid-August is the time to collect leaves for foliar nutrient sampling. The UVM Agriculture and Environmental Testing Lab can provide analysis, but at this time their output does not generate fertility recommendations. The following are potential options of labs for analysis. It is recommended that you contact the lab for instructions and costs before samples are sent. Plus, it is important to confirm that they will send recommendations along with the analysis.

(1) University of Maine Analytical Lab: http://anlab.umesci.maine.edu/
(2) University of Massachusetts Soil and Tissue Testing Lab: http://www.umass.edu/plsoils/soiltest/
(3) Cornell Nutrient Analysis Lab: http://cnal.cals.cornell.edu/

Finally, anyone interested in seeing what we’re up to in our research orchards can attend the UVM Hort Farm research day on August 6. I sent a flyer in a previous email this morning. We’ll only be covering apples from 10:30-11:15, but there will be plenty to see along the tour route and you can always chat with me before/after, at least until I need to get ready for my next stop. http://www.uvm.edu/~hortfarm/documents/20190806_UVM_HREC_ResearchDay.pdf

Where trade names or commercial products are used for identification,

no discrimination is intended and no endorsement is implied.

Always read the label before using any pesticide.

The label is the legal document for the product use.

Disregard any information in this message if it is in conflict with the

label.

The UVM Tree Fruit and Viticulture Program is supported by the

University of Vermont Agriculture Experiment Station, a USDA NIFA E-IPM

Grant, and USDA Risk Management Agency Funds.

UVM Horticulture Research & Education Center Research Open House August 6, 2019.

By Terence Bradshaw

Since 1952, the UVM Horticulture Research & Education Center has hosted projects that have furthered production of apples, small fruit, vegetables, and ornamental specialty crops in Vermont and the surrounding region Join UVM faculty, staff, and student researchers on August 6 (rain date August 9) as we show off our current research projects at the UVM Hort Farm. The agenda will follow projects via a walking tour across the landscape of the 97-acre facility throughout the day from 9:00 am – 4:30 p. Attendees are encouraged to come and go to fit your interests. Pack a lunch and make a day of it, or attend just the sessions you’re most interested in. The tour is designed so that attendees can join and leave at any point to suit their interests.

A tour agenda is attached and can be found at: http://go.uvm.edu/hrecresearchday

A research synopsis can be found at: http://go.uvm.edu/catfarmresearch

No RSVP is needed, but if accommodations are required, please email Hort Farm Director Dr. Terence Bradshaw at: tbradsha.

Please distribute to your contacts as you feel appropriate.

See you on the 6th,

Where trade names or commercial products are used for identification,

no discrimination is intended and no endorsement is implied.

Always read the label before using any pesticide.

The label is the legal document for the product use.

Disregard any information in this message if it is in conflict with the

label.

The UVM Tree Fruit and Viticulture Program is supported by the

University of Vermont Agriculture Experiment Station, a USDA NIFA E-IPM

Grant, and USDA Risk Management Agency Funds.

20190806_UVM_HREC_ResearchDay.pdf

Grape canopy management

By Terence Bradshaw

High Summer is here, and this period from after July 4 through early August is the perfect time to apply some canopy management to the vineyard. By thinning and positioning shoots; removing unwanted clusters; and cleaning up trunks, we can significantly increase penetration of sunlight into the canopy and especially into the fruiting zone. This will make for measurably better juice and wine quality, improved winter hardiness, and less disease pressure.

There are a number of practices that should be performed, but the most important is shoot positioning (also known as “combing”). This practice includes separating each shoot from its neighbor and directing the growth into the vertical plane: usually down, for high-wire cordon vines, or up for those on a low wire, vertical shoot positioning system. Once shoots are pointed in the right direction, it’s easy to see where runty secondary or tertiary shoots are in the canopy, and where smaller clusters that are behind in development compared to the main crop are- those can both be removed.

(Retired) Iowa State Extension Specialist Mike White presents a good overview of the concepts and practices behind canopy management in his February 8, 2012 newsletter found here.

There’s a video of some UVM staff doing some (silent) canopy management here.

Ohio State Extension has a nice video here.

While I have you, it’s worth mentioning that we’re not out of the woods as far as disease management is concerned. It has been a difficult year so far with all of the rain, and the frequency of it, to maintain fungicide coverage but I have been seeing mostly clean fruit and foliage in vineyards which have maintained an appropriate spray schedule of 4-5 well-selected and –timed fungicides since prebloom. At this point, phomopsis is pretty much done, and black rot will soon be winding down. Powdery and downy mildews (PM?DM) should be the main focus for disease management, as well as botrytis a few weeks down the road. If this wet weather continues, I would recommend a specific botrytis material such as Flint, Rovral, Vangard, Endura, or Pristine before bunch closure (the point where berries size up to the point where spray material cannot penetrate the cluster to protect fruit from infection). As always, check your Pest Management guide (New York & Pennsylvania or New England guides) and the label, rotate fungicide classes to reduce resistance likelihood, and follow all safety precautions when spraying. Organic disease management spray options include copper (DM, a little PM), sulfur (PM), stylet oil (PM, do not spray before or after a sulfur spray), and possibly some of the biologicals but I don’t know enough about them in regards to their performance against these late-season diseases.

Next week would be a good time to scout clusters for grape berry moth (GBM) webbing which could suggest a need to treat for that insect pest. The threshold for treating this generation is 6% of clusters showing damage, which appears as small bits of webbing in between berries up inside the cluster. GBM is the primary insect pest of established vineyards in Vermont, and if it is the only pest insect need to manage, then some very specific materials with low potential for non-target effects may be used, including lepidopteran-specific materials like Bt, Intrepid, Delegate, or Altacor (the latter has some activity against Japanese beetle). Bt (DiPel and others) and Entrust would be effective materials against GBM for organic growers- the former affects only lepidoptera, while the latter would have some activity against Japanese beetle and some other insects as well.

Where trade names or commercial products are used for identification,

no discrimination is intended and no endorsement is implied.

Always read the label before using any pesticide.

The label is the legal document for the product use.

Disregard any information in this message if it is in conflict with the

label.

The UVM Tree Fruit and Viticulture Program is supported by the

University of Vermont Agriculture Experiment Station, a USDA NIFA E-IPM

Grant, and USDA Risk Management Agency Funds.