Addressing Syrah Decline (or, If You Change Your Mind...)
June 17, 2016
OK, maybe I should have picked a different title, just so that I wouldn't have ABBA running through my head for the rest of the day. But it seemed appropriate.
We have been concerned with low yields on our Syrah. Typically a pretty vigorous producer, our Syrah yields have declined more than the rest of the vineyard, from an average of 3.4 tons/acre between 2003 and 2008 to just 2.2 tons/acre since 2009. Some of this can be attributed to the frost years of 2009 and 2011, and the drought we've seen since, but even in the otherwise vigorous year of 2012 yields were just 2.6 tons/acre, and they declined all the way to 1.5 tons/acre last year. Low yields in Syrah are a particular concern because typically we prefer it with somewhat higher yields, which can soften its often-powerful tannins and increase its complexity by lengthening its hang time.
Our largest and oldest block of Syrah, on the western edge of our original property, seems most to blame. We attribute its decline to at least two issues. Much of the block is low enough, and on flat enough ground, that it gets frozen even when most of the rest of the vineyard escapes. While a grapevine generally recovers after a single frost, repeated frosts, year after year, can lead to significant vine mortality. And so it was in this block. Compounding its problems, that Syrah block has also shown significant symptoms of trunk diseases, where fungal infections get inside the bark and gradually choke off the vine's ability to nourish the new growth further down the cordon. This has led to additional vine mortality, as well as decreased yields in the remaining vines.
Although we think we've mitigated the trunk disease issue by switching that Syrah block to a new trellis system that produces new growth each year rather than relying on the same cordons, there are so many missing and weak vines that we have decided that the only real solution is to pull the block out and start over. But even with its declining yields, that block still accounts for roughly half our Syrah production each year. So we've been struggling with when to pull the plug over there and wait out the 4 years it will take to get the vineyard replanted and in production, and what to do to keep our Syrah crop reasonable in the interim.
Our solution: graft over a two-acre Roussanne block to Syrah, and get that in production before we pull out the old block. We've got plenty of Roussanne -- about 16 acres overall -- and often find in our white blending that we have surplus to what we really need. We looked in April at the different Roussanne blocks to see if we could find one that we wouldn't miss too badly if it went away. And there is such a block, which over the last several years has usually finished toward the bottom of our rankings in the blind varietal tastings that we do to start each blending session.
Step one in the changeover was to go through and cut off the tops of the existing Roussanne vines, which we did in early May. We then let the vines bleed for a few weeks to reduce the sap pressure that can interfere with the connection between the new buds and the existing trunk:
Next, we came through (the photo below is from mid-May) and cleaned up the vine tops, peeling back the bark to allow a clean graft:
Then, two weeks ago, we brought in a specialist grafting crew to come through, cut little wedges out of each Roussanne trunk and shape Syrah buds to fit into the wedges, slot the buds in place and tape the graft unions together:
Now, 2 weeks later, the buds are starting to sprout:
This year, we'll let the new bud grow into a cane, and over the winter we'll start to train it into the shape we'll want for the finished vine. We won't get any crop this year, but we will get a small crop next year and a full crop, supercharged by the 20-year-old vine roots, the year after. We did the same thing with our old Chardonnay block in 2013 -- grafting half of it to Mourvedre and half to Counoise -- and got a good crop off of that block last harvest. One of the Counoise vines today:
If you're interested in seeing this in action, check out the video we made in 2013 of that Chardonnay/Counoise changeover. The voice you hear is our former Viticulturist Levi Glenn, explaining:
What will we do with the old Syrah block? We're not sure yet. Given its tendency to be frost prone, at least in the lower parts of the block, It's probably not ideal for the early-sprouting Syrah. But for something like Mourvedre? That seems like a slam dunk. Stay tuned.