Dr. James A. Wolpert

Viticulture Extension Specialist

Ph.D., Horticulture, Michigan State University, 1983
M.S., Horticulture, Michigan State University, 1978
B.S., Horticulture, Purdue University, 1973

Office: 2146 RMI North Building
Phone: 530-754-6245
Fax: 530-752-0382
Email: jawolpert@ucdavis.edu

Dr. Wolpert joined the Department of Viticulture and Enology in 1985. As an Extension Specialist, he is responsible for applied research and grower education programs for northern California. He has two focal points to his research: evaluation of winegrape varieties and clones and the evaluation of rootstocks. Choice of both scion and rootstock are critical decisions in vineyard establishment. His work in rootstock evaluation throughout northern and coastal California has provided the basis for grower recommendations for a range of soil types. Clone selection decisions are complex and involve marketplace targets, "wine quality," and other subjective considerations. His clonal evaluations include work on Chardonnay and Pinot noir for sparkling wine, as well as Cabernet Sauvignon, Merlot, Malbec and Zinfandel, allowing growers some insight into making those difficult decisions. Over the past decade, Dr. Wolpert, with several UC farm advisors and emeritus specialist A. Kasimatis have identified and collected selections of Zinfandel from old vineyards, many dating to the end of the 19th century or early 20th century. The project has two goals: 1) conserving potentially valuable selections that are at risk from economic pressures to replant to newer, more productive vineyards, and 2) identifying selections with better winemaking attributes (better color and varietal character, and looser, less rot-prone clusters). The Zinfandel Heritage Vineyard at the department's Oakville Station vineyard in Napa Valley is investigating viticultural and enological characteristics of advanced selections of Zinfandel taken from their original collection.

Benz, M.L.J., M.M. Anderson, M.A. Williams, K. Barnhisel and J.A. Wolpert. 2006. Viticultural performance of six clones of Merlot in Oakville, Napa Valley. American Journal for Enology and Viticulture 57:234-238.

Mercado-Martín, G.I., J.A. Wolpert, and R.J. Smith. 2006. Viticultural Performance of eleven clones and two field selections of Pinot noir for sparkling wine in Carneros, California. American Journal for Enology and Viticulture 57:371-376.

Benz, M.L., M.M. Anderson, M.A. Williams and J.A. Wolpert. 2007. Viticultural performance of three Malbec clones on two rootstocks in Oakville, Napa Valley, California. American Journal for Enology and Viticulture 58:262-267.

Anderson, M.M., R.J. Smith, M.A. Williams, and J.A. Wolpert. 2008. Viticultural evaluation of French and California Chardonnay clones grown for production of sparkling wine American Journal for Enology and Viticulture 59:73-77.

Anderson, M.M., R.J. Smith, M.A. Williams, J.A. Wolpert. 2008. Viticultural evaluation of French and California Pinot noir clones grown for production of sparkling wine. American Journal for Enology and Viticulture 59: 188-193.

Lambert, J.-J., A. J. McElrone, M. C. Battany, R.A. Dahlgren and J. A. Wolpert. 2008. Influence of soil type and changes in soil solution chemistry on vine growth parameters and grape and wine quality in a central coast California vineyard. Proceedings of the VIIth International Terroir Congress. Nyon, Switzerland, May 19-22, 2008.

Lambert, J.-J., J.A. Wolpert, M.M. Anderson. 2008. Vineyard nutrient needs vary with rootstocks and soils. California Agriculture 62:202-207

Myers, J.K., J.A. Wolpert, G.S. Howell. 2008. Effect of shoot number on shoot growth and leaf area of young Sangiovese grapevines. American Journal for Enology and Viticulture 59:422-424