Cu or not Cu

Things are looking a mite uncertain in the EU right now – at least if you’re an organic wine producer. The reason? The European Food Safety Authority is considering further restrictions on the use of copper sulfate.

Copper sulfate has been used by vintners since at least the 1880’s as a way to control downy mildew, a nasty little microbe that attacks the leaves of plants. Left unchecked, it quickly destroys the leaf canopy of the infected plant and leaves the fruit exposed to direct sunlight, a big no-no for most wine grapes. There are chemical sprays that can inhibit the mildew, but if your goal is to be an organic or biodynamic wine producer, that’s out of the question.

So if copper sulfate has been around so long and used so successfully, why is the EU taking a look? In part because of the rapid rise in the current use of copper sulfate. The compound is no longer used just in vineyards. Farmers producing organic potatoes, tomatoes and even apples have used copper sulfate. But copper is a heavy metal and is considered toxic in large doses or continued exposure. While the average wine drinker is unlikely to receive a toxic dose, those who work the fields face a constant and much larger amount. That doesn’t even include the dangers to birds and other wildlife, as well as the soil itself. Long-term exposure to copper can turn otherwise fertile land into an arid wasteland where nothing grows.

The current law allows vintners to spray about five pounds of copper sulfate a year per acre but there’s also an out for wetter years when the threat of mildew is high. This “smoothing mechanism” allows growers to spray up to twenty-seven pounds per acre over five years. So if you have a really wet year followed by a couple of average years, you can average out your usage. For areas prone to wet conditions, this has been a lifesaver. The proposed new rule, however, would drop both numbers – to 3.5 pounds per acre per year and an average over five years of twenty-five pounds per acre.

Organic and biodynamic wine makers have predicted a sharp drop in the number of farms that will be able to stay in business as an organic/biodynamic winery if the proposed rule changes are made. Yet many wine producers agree that something needs to be done. Using grapes that are less susceptible to mildew in areas subject to wet conditions is one solution that’s often given, even if that means changing some of those traditional blends a bit. Many growers have started looking to other agricultural industries for ideas, including essential oils, bacteria and even orange peel spray. The French government has also taken on the challenge, investing heavily in the hunt for grape vines that are resistant to downy mildew.

So what does all this mean for wine drinkers? In the short term, not much. If the rules passes, you may indeed see some organic producers either shift towards chemical usage or simply close up shop, but there will still be wine production, and there will still be organic wine production. Expect wetter areas, like Burgundy, to be harder hit than drier regions, like the Rhône. In the longer term, however, there could be some real changes to the wines you drink. Traditional grapes may not fare as well in their region, especially as climate change begins to have a larger impact on the weather and soil conditions of the area. Growers, especially those who use organic or biodynamic techniques, will have to change the types of grapes they have in their vineyard. It’s quite possible that fifty years from now the traditional wines we love so much today like Burgundy and Bordeaux will have little in common with their future selves.

Ah, c’est la vie. What else can one do but sip a glass of wine.

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s