Joe’s Winemaking Notes: February 2016
Vineyard Notes: Pruning
Mid-winter in our estate vineyard has kept Vineyard Manager Alvaro Zamora and his crew very busy! Dodging raindrops, they’ve been finishing pre-pruning of all vines. It’s been drier than anticipated over the past week, so both the Chardonnay and Pinot Noir have been tackled. The results are dramatic!
Most of the fresh growth from 2015 has been trimmed off, and canes have been removed from the trellis wires. Last spring and summer, these woody canes were green shoots receiving much of the vines’ energy as they grew. Although the pruning looks severe, it’s similar to the vines having a haircut, which we know grows back!
Why do we prune the vines so aggressively each winter? One big factor in determining vineyard balance is the ratio of vegetative growth to fruit. We can manage this by leaving the proper number of fruitful buds on each vine, knowing that each bud will produce one shoot and approximately two clusters. By managing our bud counts and factoring in expectations for the upcoming growing season, we can hang the proper amount of fruit on each vine.
Here’s a picture of our Chardonnay vines, with the initial pre-pruning done. You can see the established cordon (the horizontal arm that carries the fruiting buds) on spurs (the canes that are shortened for one to five nodes). Each of our spurs holds two buds, resulting in two shoots and four clusters for each spur.
Now, here’s a picture of one of our Pinot Noir vines, and you can see a different technique used. This style of pruning is called cane pruning. We’re in the process of converting all our Pinot Noir to cane pruning, for a number of reasons. Cordon pruning was in vogue in the 1990s and early 2000s, when our vineyard was planted. It was planted this way due to the simplicity it afforded our vineyard crew. Once the cordons were established in the second and third years after planting, it became a simple matter of trimming off the shoots and leaving a two bud spur where the previous year’s spur was. A large percentage (likely a majority) of high quality vineyards throughout the Russian River Valley are still trained with this cordon style. There are few downsides to cordon pruning, however. These are driving the changes at The Rubin Family Vineyards and Winery.
First, control of yields in the vineyard is easier with cane pruning. We can leave two or three canes on the vines after pruning, each with up to 10 buds. These numbers can be varied with the visible strength of the vine by looking at the previous year’s growth. After bud break, if we see great potential fruitfulness and fruit set after bloom appears good, we can remove excess clusters to maintain the right balance. With cordons, we have experienced more variation in yields, with a poor yielding vintage like 2015 causing much more disruption in the cordon trained blocks. The trial blocks that we converted to cane pruning before last year performed quite well!
A second big reason for transforming our Pinot Noir to cane pruning is the presence of a vine trunk disease called Eutypa. A fungus transmitted from vine to vine during rainy periods, Eutypa infection tends to happen during our pruning season. The fungus is widespread throughout California, and causes dead arm disease on grapevines. After infection, either portions or entire cordon arms will die back. This continues to destroy the vascular system of the vine, down the trunk of it. Eventually the entire vine will die. Controls for this fungus include applying fungicide paints on pruning cuts (just as you might do to your fruit trees), as well as removing dead arms, and training new cordons in their place. The vine may remain unbalanced, however, and grape ripening within the block may lack the uniformity I seek.
Our Chardonnay appears to be more resistant to outbreaks of Eutypa, so we’re maintaining a cordon pruned style. On Chardonnay, this gives us the right mix of yield, cluster separation, and flavors. When growing grapes, every vine has its unique demands!
Unified Wine Grape Symposium
Late January always includes attendance at the Unified Wine and Grape Symposium, the largest and most important trade show for the American wine industry. The winemaking team was present for seminars and to explore the newest technology in winemaking. It’s quite an experience, showcasing the many ways that we can continue to innovate!
In The Wine Cellar
We’re keeping up with the topping-off of barrels, and we’ve begun identifying the best Russian River Valley Chardonnay lots for our Ron Rubin Russian River Valley Chardonnay bottling. Bottling is scheduled for May. The character of each individual wine is becoming apparent, but each one will remain in barrels for another two and a half months, to further become more. So far we’re very pleased, and will have quite a showy Chardonnay for you to taste in 2017!
We’re also meeting with many of our grape growing partners, who represent the entire range of appellations in Sonoma County. We love the times spent tasting the young wines and discussing the successes of the past vintage. Sonoma County boasts a passionate group of winegrowers, and we’re fortunate to partner with many of them to produce our Ron Rubin, Pamela’s, and Pam’s Un-Oaked wines!