Each year the San Joaquin Valley Winegrowers Association (SJVWA) honors industry icons for their contributions to the success of the wine grape production. This year the group lauded a grape grower and two University of California researchers for their achievements.
Ken Yonan, a San Joaquin Valley grape farmer and founding board member for the SJVWA; Walt Bentley, a retired farm advisor and entomologist; and Doug Gubler, a retired Cooperative Extension plant pathologist; each were recognized by the association during the group’s annual industry forum in Fresno, Calif.
Combined the trio have about a century’s worth of experience in wine grape production and are responsible for at least some of the success the industry enjoys today.
Yonan spent much of his life working in the vineyards – first in his father’s grapes then later in his own Thompson, Chardonnay and Merlot vineyards.
He is a founding board member of the SJVWA and a longtime member of Allied Grape Growers.
From a young age Yonan was in the field with his father learning the business of growing grapes.
Yonan grew up in Stanislaus County, attending school in Keyes and Turlock before studying at Modesto Junior College. Like many farm children in the day he spent his time before and after school working on the farm, pruning, tying and weeding in the vineyards.
While attending college Yonan’s father, Keena, added 40 acres to a flourishing 25-acre block of grapes. A year later, in 1962, Yonan sought work in San Francisco to help the family with land payments. He worked during the week with Pacific Bell, returning to the family farm on the weekends to work the vineyard.
In 1964 Yonan was drafted in the Army. Two years later he returned to the family farm and his job at Pacific Bell.
By 1974 Yonan would meet Laura Dale Shiver and the two would be married. Shortly thereafter the couple moved to Turlock where he continued his two jobs – the telephone company and the family farm with his father. He worked beside his father until his passing in 1985. Yonan remained with Pacific Bell until his retirement in 1990.
Yonan’s first wife and his mother died four years later. In 1995 he married his current wife, Wendy.
Following retirement Yonan replanted 45 acres of Thompson grapes to Chardonnay and Merlot.
Yonan’s health keeps him out of the fields these days, but not inactive in the business. His son Keena continues with the day-to-day family operations, still keeping his father informed and seeking his input.
Bentley spent 35 years with the UC Cooperative Extension, first as a farm advisor in Kern County; later as an integrated pest management (IPM) advisor at the Kearney Agricultural Research and Extension Center in Parlier.
He retired from his position in 2012.
Bentley’s work includes collaborating with various university and U.S. Department of Agriculture researchers on a host of challenging pest issues. He authored 65 chapters or sections in pest management manuals and 75 peer-reviewed articles during his career.
His writings include more than 250 articles that appeared in trade journals and newspapers.
Bentley’s academic career began after earning his bachelor’s degree in horticulture and biology in 1969 from Fresno State University. He spent two years in the Army working on tracing mosquito movement in Texas, Oklahoma and Utah.
In 1974 he earned a master’s degree in entomology from Colorado State University, later working for the Colorado Department of Agriculture before returning to his native California, where he went to work in Bakersfield with the University of California Cooperative Extension.
Through his career Bentley collaborated with IPM and commodity-specific farm advisors and specialists to develop IPM approaches and control strategies that led to the significant reduction in use of carbamates and organophosphates in grapes, almonds and tree fruit.
Some of his work included development of IPM programs for almonds, where he addressed control of spider mites, Navel orange worms and ants. He also worked on projects to monitor and control the potato tuber moth in potatoes.
Bentley grew on his family’s cherry, walnut and peach farm in the San Joaquin County community of Linden. His post-retirement time is spent in part making hand-tied flies used to catch and release trout.
Gubler’s 33-year career with the UC Davis as a Cooperative Extension plant pathologist focused primarily on the management of diseases and their impacts on grapes, apples, stone fruit and strawberries.
His research looked into the efficacy of fungicides that later helped define best management practices for controlling powdery mildew and other diseases. Without his fungicide evaluations, growers would have been forced to design management programs based on trial and error.
Like Bentley, Gubler’s efforts led to the reduction in pesticide usage through improved disease control.
He is known for his work in botrytis in grapes. His epidemiological approach to disease control and canopy management focused on improving air movement within the grape canopy by removing leaves and shoots that helped dislodge dying flower parts contributing to the disease.
This is now a common cultural practice in vineyards around the world.
Gubler is also known for his powdery mildew risk index. This system relies on data from weather stations within vineyards that is used to determine the risk of powdery mildew.
Because of Gubler’s work, this disease-forecasting model is now part of the software in major weather stations used by grape growers around the world. This has helped greatly reduce and eliminate fungicide applications, saving growers money the world over.
Gubler earned his bachelor’s degree in botany and zoology in 1970 from Southern Utah State College. He earned a master’s degree in plant pathology from the University of Arkansas and later his Ph.D. from UC Davis.
Prior to joining the Department of Plant Pathology at UC Davis in 1983 Gubler worked with the Campbell Soup Institute for Research and Technology.
He currently holds a lecturer appointment in the UC Davis Department of Plant Pathology and is active in the education, training and mentoring of graduate students.