Current UC Viticulture Research
|Principal Investigator||James Wolpert|
|Project Title||Evaluation of Zinfandel Heritage Selections|
Zinfandel selections from throughout the state were collected and placed in the Zinfandel Heritage Vineyard at the Oakville Station in Oakville, California. The geographic range increases the possibility of finding selections that are unique and useful. This project describes the selections in terms of viticultural characteristics.
This is a large replicated trial that was originally planted with 22 Zinfandel selections on 2.4 acres. The replicated design of this trial provides more robust data than the original unreplicated collection. The Phase 2 vineyard includes selections that were determined to be virus-free and from unique vineyards. Leafroll type 2 was subsequently found in three selections, reducing the total selection number to 19 upon their removal.
Mean data from multiple years is more accurately descriptive of the selections than individual years. The dataset includes four years except for pruning weight, which covers three years data. Mean yield over those years ranges from 3.3 to 5.3 kg per vine. Berry weight is very similar for all selections at approximately 1.8 grams per berry. Cluster number per vine is similar, for the most part controlled by the fact that all selections are pruned to the same bud number. Yield differences are therefore most influenced by berry number per cluster. Berries per cluster range from 113 to 170 over the four years. Selections are harvested at a pre described Brix, so there is little range in that value. Two selections however do appear to be earlier maturing; they are also the two lowest yielding. None of the selections are distinguishing themselves in terms of pH or TA.
Details and progress reports from the Zinfandel Heritage vineyard Project can be accessed here.
Video presentation of Dr. Wolpert describing his work at the 2007 UC Davis Extension seminar "Variety Focus: Zinfandel." Video may take a few minutes to begin but does not require additional software.
|Researchers and Cooperators|
Wolpert, J and Anderson, M. The Zinfandel Heritage Vineyard Project 2010 Report (pdf).
Wolpert, J. 1996. Performance of Zinfandel and Primitivo clones in a warm climate. Am. J. Enol. Vitic. 47(2):124-126. Abstract
Zinfandel Advocates & Producers Preserving Heritage, Promoting Excellence: The Zinfandel Heritage Vineyard Project (pdf). The Zinfandel Chronicles. Available online here.