Researcher Spotlights

Brent Holtz

Brent Holtz is a farm advisor and the cooperative extension County Director for San Joaquin County.

What led you to become a farm advisor?

I worked with farm advisors while in graduate school and I thought they had a great job being able to work with both growers and university researchers.  I liked the idea of extending research generated at the university to farmers in the field.  I like being out in the field working with growers, helping them solve everyday problems…. to find more sustainable farming practices. 

My research and extension programs have had one underlying theme; that is to help deciduous tree fruit growers in production agriculture find more environmentally friendly ways to produce their crops without compromising product quality or price.  As a Pomology Farm Advisor, I deliver a research and extension program focused on sustainable production. 

What brought your work to Kearney REC?

I first came to Kearney REC as a post-doc for Dr. Michailides in 1993, almost 30 years ago, researching brown rot of stone fruits.  I later returned to Kearney with a project in 2008 when I recycled my first orchard with the Iron Wolf, a 100,000-pound rock crusher.  Whole Orchard Recycling involves grinding whole trees into wood chips, spreading the wood chips evenly on the soil surface, and incorporating them into the soil before replanting. This approach is a potentially sustainable method of tree removal that could enhance both air and soil quality. 

What do you hope to learn from your research at Kearney REC?

In this first whole orchard recycling project, I compared the grinding and incorporation of whole trees into the soil, estimated at 60 tons per acre, with burning the trees and spreading the ash.  Second-generation almond trees were planted in both treatments and I evaluated tree growth, disease, soil fertility, yield, and the nitrogen to carbon ratio.  A decade of observations showed trees growing in the recycled orchard had greater yields, significantly more soil nutrients, soil organic matter, total carbon, and increased water holding capacity! 

What is your favorite part about conducting your research at Kearney REC?

I like coming to Kearney because I can escape from my office and do fieldwork!  I also enjoy seeing other researchers at Kearney, talking about our projects, and being part of the camaraderie that has made the Kearney REC such a wonderful place to work. 

***The almond board recently honored Brent's work with whole orchard recycling with this video.***