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28 WINES&VINES May 2016 B ud break and young shoot growth occurs rapidly across winegrowing regions, and warm temperatures hasten the workload for vineyard-management crews. Canopy man- agement, shoot thinning and selective shoot removal are on the minds of most growers at this time. It is easy to get lost in the details of the next task when shoots are growing rapidly, but let's not miss the opportunity to take a critical look back at the pruning work that has occupied the past few months. Pruning is arguably the most important vineyard task. If done properly, it will greatly improve vineyard manage- ment during the season. A critical assessment of your prun- ing job is best accomplished between bud break and bloom. Hence, the proof of success of your pruning strategy is by now (or soon will be) evident. Bud count vs. shoot number Realistically, no experienced pruner will take the time to count buds on each final pruned vine. When training new pruning crews, I often suggest they count buds on the first 20 vines pruned to calibrate their eyes. After the eye is trained, an occasional follow-up count on a vine will help test their proficiency. Within a few weeks of bud break, we can truly assess if the bud number retained per vine resulted in a similar number of shoots. When leaving two count buds on a spur, we expect see two fruitful shoots developing from that spur. The disagreement from bud count to shoot number often occurs when the pruner does not properly identify count vs. non-count buds (see photo at right). Distinguishing count buds can be a challenge for new growers, which is why it can be very helpful to look at what sprouts out of the vine this time of year. Count buds are the fruitful buds retained during dormant pruning and derived from node positions distinctly separated from wood that is two years old or more. Non- count buds are smaller and located where the one-year-old wood con- tacts older wood. They have po- tential to produce shoots that are typically non-fruitful. Fruitfulness of buds is in part determined by genetics, but other factors such as freeze damage, vine nutri- tion, virus and poor weather conditions during bud devel- opment in the previous season can affect the survival and fruitfulness of a primary bud. Some varieties are also notori- ous for pushing non-count shoots, such as French-American hybrids Seyval Blanc and Chambourcin. If follow-up counts are made on a few vines per block, after a few years of observation one can adjust bud counts to better target the resulting number of fruitful shoots for each variety in the vineyard. Bud counts at pruning time can then be adjusted up or down to achieve the target shoot density and yield more closely. Shoot distribution uniformity Part of the art of dormant pruning is not only eyeballing the proper number of count buds, but also retaining them in a way that promotes uniform distribution of shoots along n FRITZ WESTOVER The Proof Is in the Pruning: Early Season Canopy Assessment Grapegrowing Small lateral shoots with diameters thinner than a pencil (above left) should be removed when pruning (above right). Count buds are identified in green, while non-count buds are red.