Net Loss for the Environment: The Burning of Vineyard Vines Makes a Less Sustainable Wine
A long-time resident of Calistoga recently told me of a time before the Clean Air Act when smog from San Francisco Bay would blow up the Napa Valley, tinting the sky with a lovely russet hue. Now it seems that the largest threat to air quality in many wine regions (besides the obvious automobile traffic) are the seasonal bonfires that are used by vineyard managers to eradicate the bulk of vines and prunings during the late fall, winter, and early spring months.
Grape farmers tend to burn vineyard wastes to ensure that no undesirable molds or pests like the glassy-winged sharpshooter or the European grapevine moth survive to pass their spawn into a new era of grape vine degradation. For an industry that should be concerned about climate change, it would seem logical for winegrowers to do their part in limiting the greenhouse gas emissions from burning large piles of waste. And for communities that are generally concerned about maintaining a healthy lifestyle, I am surprised at the residents of Napa County who are willing to breathe the particulate matter (PM) from these fires as if it were a badge of honor.
It somehow reminds of when Bill Richardson as Secretary of Energy once “honored” the workers of the nuclear bomb facility in Paducah, Kentucky as “Heroes of the Cold War” for unknowingly being exposed to radioactivity at very high levels in their workplace and then prematurely dying of cancers. I realize this analogy is a bit extreme, but the premise and underlying question is the same: does turning one’s head the other way and absorbing a cost to your heath in order to make a short-term buck make you a hero?
The Particulars of Particulates
Exposure to PM levels exceeding regulatory standards is associated with increased risk of hospitalization for lung and heart-related respiratory illness, premature deaths in the elderly and people living with pre-existing cardiopulmonary disease, reduced lung function and illness in children, and harm to crops, forests, aquatic, and other ecosystems from the nitrates and sulfates in the PMs.
Regulators often focus on PM emissions in two sizes: PM10 and PM2.5 - which are about 10 and 2.5 micrometers in diameter, respectively. Particle size is important because determines where in the respiratory tract the particle will likely come to rest if inhaled. PM10 can get into the bronchioles or alveoli and cause health problems, whereas PM2.5 can penetrate the gas exchange regions of the lung and may even pass through the lungs to affect other organs.
There is an air quality monitoring station that represents the entire 28 miles of Napa Valley on Jefferson Avenue in the City of Napa. This location is listed as a non-attainment area, an attainment area, and an unclassified area for PM10 depending on particulate size and which regulator you ask: unsurprisingly, California standards are stricter than the national standards. We’ll get to PM2.5 in a moment.
The Bay Area Air Quality Management District (BAAQMD) is the organization in charge of regulating open fires in Napa. Their regulations note that the Air Pollution Control Officer can halt burnings “when negative impact upon public health is anticipated.” (S. 5-223) More specifically, a negative impact is when PM2.5 levels are forecasted to exceed 35 micrograms per cubic meter. (S. 6-3-203) While this regulatory device for moratoria is a lovely thought, there is no PM2.5 monitoring in Napa Valley or most rural vineyard areas in the State of California. No PM2.5 measurements = effectively useless curtailment regulations far as rural burning of vineyard wastes are concerned = unknown levels of PM2.5 travel into the organs of Napa residents.
It’s probably safe to say that Napa isn’t a top priority for BAAQMD, which considers the lack of sources of pollutants in the air basin small potatoes in comparison to more densely populated and industrial places to the south. Of course, air pollution may blow north and can be trapped in geographical nuances within the narrow confines of the Valley – and of this BAAQMD is aware:
“Air pollution potential is high. Summer and fall prevailing winds can transport non-local and locally generated ozone precursors northward where the valley narrows, effectively trapping and concentrating the pollutants under stable conditions. The local upslope and downslope flows setup by the surrounding mountains may also recirculate pollutants adding to the total burden. Also, the high frequency of light winds and associated stable conditions during the late fall and winter, contributes to the buildup of particulates and carbon monoxide from automobiles, agricultural burning and fireplace burning.”
I’m not saying that California hasn’t done a tremendous job in ratcheting down air pollution standards for its citizens in comparison to the rest of the country – it has. Nor am I advocating that it should place air quality monitors for PM10 and PM2.5 in every nook and cranny of the Napa Valley. At the risk of saving regulatory costs, increasing public health and putting a couple of public servants out of a job, I do submit that that it makes better sense to prohibit vineyard burns when there is a more sustainable option.
What Are the Alternatives?
Let’s start with the U.S. Department of Agriculture (USDA). The USDA’s Conservation Stewardship Program “encourages agricultural producers to improve conservation systems by undertaking additional conservation activities and improving, maintaining, and managing existing conservation activities.”
Shall I translate? The USDA agrees with me: when we can do better for the long-term welfare of public health and the environment, we should. And when it comes to burning vineyard material, USDA specifically suggests non-burning alternatives. More specifically, it states that “[n]on-burning alternatives would include chipping, grinding, shredding, mowing or composting these materials.” So there are a few alternatives that seem easy enough.
Is it a Waste or is it a Resource?
The Obamarama party of 2008 surely got the renewable energy industry pretty excited about legislation that would support alternative fuels and put a price on carbon. Biofuel start-ups were becoming fashionable, with a farmer in every corner of the country trying to find a feedstock and a patented organism to turn sticks and algae into a replacement for Middle Eastern conflict and a $4+ gallon of gasoline.
In a world of Obama Term One letdowns, perhaps we all took our eyes off the ball. Perhaps Craig Venter and his kind were still busy in their laboratories designing the best synthetic organism to turn woody material into cellulosic ethanol. I’d put my money on the fact that they were, as they know that a carbon economy is an eventuality and that cellulosic ethanol yields 85% less greenhouse gases than reformulated gasoline.
The Kiwis are cleaning our clocks at cellulosic sustainability in the vineyards. Grove Mill, a winery in Marlborough, New Zealand (and the first carbon neutral winery in the world) has converted one of its tractors to run on ethanol from vine prunings. The adaptation has reduced diesel consumption in the vineyard by 75%. The decision to convert the tractor was primarily economic: “When you’ve got a tractor going for six hours a day, that’s a lot of fuel and money.”
Yealands Estate Winery, also in Marlborough, recently announced its plan to burn 10% of its pruning clippings in a boiler to provide 85% of winery’s energy, foregoing continued use of petroleum. Winery owner Peter Yealands explains how he moved his winery to become the largest carbon neutral winery in New Zealand:
“The Bio-Mass Boiler has been specially designed to heat the winery’s water and glycol – a liquid that is pumped into ‘jackets’ around fermentation tanks to heat or cool the wine. This boiler will see the winery saving 22 tonnes of LPG a year, meaning our total carbon footprint for LPG will be reduced to zero …. Not only is this initiative great for the environment, it also provides evidence that sustainable wine production is commercially viable.”
So maybe most California wineries are not there yet, but a few are getting the idea. More and more wineries, from larger operations like Rodney Strong to small operations like Muir Hanna are chipping vines and clippings instead of burning, spurred on by the recognition that sustainability is a community responsibility.
This season, I have read advertisements for “The Burning of the Canes”-style parties advertised at wineries in Northern California. Frankly, a “Recycling of the Canes” party would be much more worthy of raising a glass – and a great start to a new season.
Top photo: J.L. Sousa/Napa Valley Register