The vineyards of Chablis have had a tough time this year. First they were devastated by frost, then hail and now mildew is ravaging through the region. I visited Burgundy last week as guests of Albert Bichot, who make wine and grow grapes all over the region. They told us that the downy mildew (aka Peronospora) outbreak is the worst in living memory.
Mildew thrives in humid conditions, and the lack of morning sunshine so far this summer has meant that morning dew has been lingering longer than normal. This encourages the spread of the disease, which manifests itself as discoloured patches on leaves - see below.
The result is reduced photosynthesis, retarded ripening and ultimately a lower yield of poorer quality wine. The predicted yield for their AC Chablis this year is 5 hl/ha, compared to a normal volume ten times higher than that. When the 2016 vintage reaches our shelves, it is likely to be significantly more expensive.
The only silver lining on the omnipresent clouds has been in Grand Cru Chablis, which was been less affected by the adverse weather conditions of this season. But they aren't taking any chances, and when we visited, they were spraying the vines with a copper-based solution which is used as the standard prophylactic for mildew.
Spraying this efficiently requires bespoke machinery that is pretty scary to watch in action. The slopes are so steep and closely planted that a narrow, ride-on caterpillar track sprayer is first tethered by a rope to a tractor, which then descends down the slope to spray the rows. You can see this in action in the below video - observe also the protective gear worn by the operator - these are powerful chemicals!
As if mildew wasn't enough, Bichot also have a viral problem in their monopole Moutonne Chablis Grand Cru. It can be seen in the picture below as a patch of yellow-leaved vines. They suspect the virus might be court-noué, but apparently it doesn't re-appear every year.
It's not easy being a grape grower in Burgundy right now.