April 24, 2014

Now that vines are pruned it is time to shift your thinking to under trellis weed management in the vineyard. Especially in this season where many growers will be leaving shoots low on the trunk to use as replacement parts for cold-injured vines, it is important to avoid herbicide contact with green tissue. Grapes are especially sensitive to many herbicides, so early spring before bud break is a good window for application of materials if you will be using them in the vineyard. Young vines with thin bark on the lower trunk can also be damaged by herbicide contact, so shielded sprayers or waxed trunk guards should be used.

Specific herbicide materials and their use restrictions and guidelines ca be found in Chapter 6 of the New York and Pennsylvania Pest Management Guidelines for Grapes

In February 2013, a Northern Grapes Project Webinar on vineyard groundcover management was offered that can be viewed here:
http://youtu.be/pSNy08aEs4E
Also, slides from vineyard weed identification and management presentations made to growers at the Northwest Michigan Horticultural Research Center from April 17, 2014 are available here:
http://bit.ly/1kdeGWp

The window to best manage weeds with herbicide applications is short, so please consider getting out there in the next couple of weeks. Once weeds get established in the vineyard and vines start growing, under trellis groundcover management becomes very difficult without causing vine injury.

Terence Bradshaw, UVM Tree Fruit and Viticulture Specialist

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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.