Grape E-Alert May 5th

In this alert:

On-Site Farm Visits are Still Available

Budbreak has Started

Herbicides Rotation

Sheep Grazing (your input is requested, Justine Vanden Heuvel)

Disease Management

Early Season Grape Disease Management (Katie Gold)

2020 New York and Pennsylvania Pest Management Guidelines for Grapes Available

Pest Management

Climbing Cutworms

Grape Flea Beetles

On-Site Farm Visits are Still Available

ENYCHP specialists continue to make one-on-one farm visits when requested, taking the measures appropriate to ensure the safety of all concerned. As always, specialists are available to answer your questions via text, email, and telephone. Group meetings are currently restricted, with an increased emphasis on online material and forums. Stay tuned for more information about online events, including meetings with pesticide recertification credits.

Budbreak has Started

A milder than average winter was suggesting an early budbreak, but a cool spring has put growth back on an average track. Marquette budbreak was seen on May 2 in a Lower Hudson Valley vineyard with 28 GDDs. In 2019, the same vineyard had budbreak on April 21 with 81 GDDs. In 2018, budbreak was May 4 with 80 GDDs. These differences highlight some of the complexities of bud development with respect to temperature -- what happens before seasonal GDD accumulation is just as important. Pinot Noir and Cabernet Sauvignon has also reached budbreak in Lower Hudson Valley.

GDD accumulation in Champlain Valley is on par with 2019, but the remainder of Eastern New York is behind (see maps linked here):

Growing Degree Days and Precipitation: YTD

Differential Growing Degree Days and Precipitation: YTD vs 2019

Herbicides

Rotation

Broad spectrum products Chateau (flumioxazin) preemergent and Roundup (glyphosate) postemergent are a popular combination, but should not be the only tools employed. For those not on Long Island, Rely 280 (glufosinate-ammonium) is also a broad spectrum herbicide and can be used in rotation glyphosate while also useful in sucker control. Other of products with narrower efficacy can also be used in combination [e.g. Poast (sethoxydim) for broadleaves and Aim (carfentrazone-ethyl) for grasses].

Sheep Grazing

Still dreaming of herbicide free viticulture? The Vanden Heuvel viticulture research program is conducting a survey to determine grower perceptions of using sheep to mow/sucker in vineyards. Your input is requested: Research Survey: Mowing and Suckering with Sheep, Justine Vanden Heuvel, Cornell University

Disease Management

Early Season Grape Disease Management

Cornell’s new grape pathologist, Katie Gold, has written an excellent overview of grape disease management concepts and best-practices. The report covers early season concerns, particularly the importance of acting early to reduce problems later in the season. She plans to release a follow up report for later season concerns: Early Season Grape Disease Management, Katie Gold, Cornell University

2020 New York and Pennsylvania Pest Management Guidelines for Grapes Available

The 2020 New York and Pennsylvania Pest Management Guidelines for Grapes is now on sale and is available for purchase at https://www.cornellstore.com/books/cornell-cooperative-ext-pmep-guidelines.

Pest Management

Climbing Cutworms

Buds are susceptible to damage from climbing cutworms between bud swell and 1" shoots. When scouting look for grey larvae about 1 - 1.25" long. The recommended economic injury level to justify spraying is 2% bud damage. For more information on the life cycle and management of climbing cutworm, see https://ecommons.cornell.edu/handle/1813/43085

Grape Flea Beetles

Buds are susceptible damage from overwintering adult beetles during bud swell. Look for shiny blue beetles approximately 1/4" long Note that most/all insecticides labeled for grape flea beetle are also labeled for climbing cutworms, but the reverse is not true. For more information on the life cycle and management of grape flea beetle, see https://ecommons.cornell.edu/handle/1813/43101