Your source for orchard news & information in the Sacramento Valley
There are those years we like to leave behind, and 2022 will be at the top of the list for the walnut industry. Read for more information on the most likely environmental conditions that led to 2022 crop damage and subsequent yield losses and poor nut quality. Continue reading
An April frost can have potentially devastating results. The last severe spring frost occurred in April 2008. During a frost event, there are many factors that influence whether or not frost damage will occur in a particular orchard. This article provides guidelines should a spring frost occur. Continue reading
Rootstocks are the foundation of a walnut orchard. Selecting one with attributes that will tolerate or resist site problems, while providing the vigor for optimum tree performance, is key to orchard health and longevity. This article provides updates from the latest rootstock research statewide. Continue reading
Because there is not a CIMIS station close to Yuba City, Janine Hasey calculates chilling based on a temperature recorder at the UCCE office in Yuba City. Chill data will be updated weekly. Continue reading
How are we doing on chill so far this year? Because there is not a CIMIS station close to Yuba City, Janine Hasey calculates chill based on a temperature recorder at the UCCE office in Yuba City. Chill data will be updated weekly. Continue reading
I am retiring on July 1st after nearly 38 years working for UC Cooperative Extension and over 36 years as an Orchard and Environmental Horticulture (EH) Advisor in Sutter-Yuba Counties. What an honor to work with all of you growers, PCAs, and others in the Ag industry, and such a privilege to collaborate with so many talented UC colleagues solving challenging problems together. Continue reading
We have been seeing walnut leaves showing browning (necrosis) on the leaf area between the veins in some orchards since about mid-May. Sometimes the leaves will then twist and defoliate in very severe situations. We call this problem mesophyll collapse and believe it is a physiological problem associated with sudden temperature changes. Continue reading
How are we doing on chill so far this year? Because there is not a CIMIS station close to Yuba City, Janine Hasey calculates chill based on a temperature recorder at the UCCE office in Yuba City. Chill data will be updated weekly. Continue reading
Since last summer, coffee shop talk has been centered on the low price of walnuts. We all hope to see improvement in pricing soon. Even if prices increase, there are cultural and pest management options to improving your profit margin. … Continue reading
Janine Hasey, UCCE Farm Advisor, Sutter/Yuba/Colusa Counties, Greg Browne, USDA Plant Pathologist, UC Davis, Astrid Volder, Plant Sciences, UC Davis and Bruce Lampinen, UCCE Walnut Specialist, UC Davis 2017 brought unprecedented high and fluctuating water flows in the Sacramento and Feather Rivers, damaging … Continue reading
Updated 10/25/18; Originally posted July 2018. Janine Hasey, UCCE Tree Crops Advisor Sutter/ Yuba/ Colusa Counties; Bruce Lampinen, UCCE Walnut Specialist, UC Davis; Katherine Jarvis-Shean, UCCE Orchard Advisor Sacramento, Solano & Yolo Cos. Early walnut tree training begins at the time of … Continue reading
Updated February, 2020. Originally posted June, 2016. Janine Hasey, Chuck Leslie, Wesley Hackett, Pat J. Brown, Andreas Westphal, Michael McKenry, Greg Browne, & Dan Kluepfel. Helpful terminology in understanding walnut plant material: Cultivar (cultivated variety) – A named group of … Continue reading
The Paradox hybrids (Juglans hindsii x Juglans regia) commonly used as walnut rootstocks are highly susceptible to Crown Gall caused by the common soil-borne bacterium Agrobacterium tumefaciens. Here we present information from our quest to develop a robust comprehensive approach to crown gall prevention. Continue reading
Training young walnut trees occurs in the first 1-6 years in the life of an orchard. Traditionally it has been done using a modified central leader with a minimum pruning style. Research conducted since 2004 investigating pruning versus non-pruning on young walnut tree growth and productivity has challenged that paradigm. Continue reading
2017 brought us unprecedented high and fluctuating water flows in the Sacramento and Feather Rivers, damaging orchards from direct flooding and indirectly via under-levee seepage. Many trees had a long exposure to waterlogged conditions through the winter and spring. This article discusses strategies for minimizing losses in 2018 in flood-impacted orchards. Continue reading