Trunk Disease, CVC Winter Spore Traps, and Prevention

Published: 2021-10-25

Cheers to a successful harvest, friends! With the 2021 season being wrapped up with erosion control and prepping for winter, we are greeted with our much-needed rain.

Winter "to do" lists for vineyards include herbicide applications/weed control and pruning. While you get your sprayers calibrated and lined up, today we will discuss pruning. Not how to prune, but the challenges trunk diseases like Eutypa and Bot Cancker pose while we are pruning.

Imagine a good day in the winter months with sunshine and clear skies. The rain has stopped, and the ground is firm enough for entry to begin pruning. Everything is great. However, there is a wolf in the sheep pen.

The unseen villain of this story is trunk disease. The spores move unseen in the air, somewhat randomly in strength/concentration, to find our susceptible pruned vines. They grow into the grapevines and wreak havoc on the plant, slowly draining it of production, quality, and eventually life. These diseases need water and an opening into the plant for entry. When grapevines are pruned, their interior tissue is exposed. The trunk disease spores blowing in the wind or splashed by rain contact the pruning wounds. The spores now have a vulnerable host and an environment to infect (sap or water from rain/dew) to begin their own life cycle of destruction.

Besides being a great band name, Euytpa and Bot Canker spore releases are not fully understood. When exactly do they begin to release spores? What weather conditions result in the highest spore counts? Where are the highest spore numbers in my vineyards? If I prune late will the spore numbers drop off? If so, when will they drop and by how much? Is one treatment each winter enough to protect my vineyard?

These questions are being answered with CVC Winter Spore Traps. CVC's standard pruning practice is to follow immediately behind our pruners with a fungicide application. With the right mixture of spreader-sticker and active ingredient, we can help prevent & eradicate spores landing in our vineyards. What CVC has learned is that the pruning day and spray day can be coordinated more effectively with the use of CVC Winter Spore Traps.

The idea is simple. With CVC Winter Spore Traps, monitor the trunk disease spores entering your vineyard, then make the decision to prune at low spore concentrations. Then when you prune, you know here is a wolf and not wolves. Meaning the disease may be present, but in much lower concentrations. Using our sustainable practices, we can reduce the risk of disease infection. As you begin pruning, remember to pay attention to the unseen wolves on the horizon. The only way to know when they are in the sheep pen, is with a tool designed to look for them.