Diseases & Pests

Diseases and Pests

Beyond the temperature considerations, grapes are also heir to a wide variety of diseases and pests. Wet weather early in the season and humid conditions through the summer can accelerate a variety of fungus infections including downy mildew, powdery mildew, botrytis bunch rot, black rot and anthracnose. Canopy management that involves shoot positioning and leaf pulling to keep the vines as dry as possible by exposure to the sun and open to breezes, as well as vineyard sanitation practices that eliminate sources of infection can help control these, but require a lot of hand work and many trips through the vineyard as the vines grow. Some vineyards take a pre-emptive approach and establish a regular spraying program. Fortunately, the cultivars that Mad River Vineyard grows that have been bred for cold hardiness also display elevated resistance to the afflictions of disease and pests when compared to vinifera or French-American hybrids.

In terms of insect pests, there are at least as many as diseases. In Vermont, phylloxera, grape berry moth, grape leafhopper, and the rose chafer can attack vines and can cause substantial damage to the crop. All require careful monitoring and constant inspection to stay on top of infestations.

However, Mad River Vineyard has found there is at least one insect that can be dealt with on a straight entrepreneurial basis. Japanese beetles love to visit us In late spring and early summer, ripping through the vineyard and reducing leaves to lacy ghosts of their former selves. The beetles are fairly large and easily seen. Joe’s approach has been to offer his grandchildren a penny bounty for each they bring in—it’s amazing how fast young ones learn how to count to large numbers and deal with financial transactions, while cleaning out the vineyard!

There are other, larger, pests that can do great damage to vineyards, especially later in the season . Birds and raccoons are known for developing a discriminating taste for grapes—attacking them just as they ripen to perfection. While we haven't yet been bothered by raccoons, Mad River Vineyard does cover its vines with netting in August before the grapes ripen. We remove them the morning of harvest to minimize damage by birds. In the past, Mad River Vineyard was a noted dining spot for the region’s robins, who fattened up nicely on the grapes.

Vermont does have some pests not likely to bother vineyards elsewhere, but we don’t suffer other problems. Growing wine grapes takes a great deal of patience, care and attention. We've carefully chosen the grapes that Mad River Vineyard grows to take advantage of their natural qualities as much as possible.