Your source for orchard news & information in the Sacramento Valley
Written by Emily J. Symmes, UCCE Area IPM Advisor; Bob Van Steenwyk, UCCE Entomology Specialist; Bill Coates, UCCE Farm Advisor Emeritus, San Benito, Santa Cruz, Santa Clara, and Monterey Counties; and Janine Hasey, UC Farm Advisor, Sutter, Yuba, and Colusa … Continue reading
Due to superior vigor, more adaptability to marginal soils, and greater tolerance to Phytophthora crown and root rot and water logging conditions, English walnut varieties on Paradox hybrid rootstock are the preference of most California walnut growers. The major disadvantage … Continue reading
Hot weather favors the fungal disease Branch Wilt (Nattrassia mangiferae, formerly Hendersonula toruloidea). Below are the main points you need to know to recognize and manage this walnut disease.
Typically in July and August after a hot spell, the first symptom of branch wilt is yellowing and browning of the outermost branches usually on the southwest exposure of the tree (Photo 1). Continue reading
Adapted from the article “Considerations When Replanting Individual Trees in a Walnut Orchard” by Carolyn DeBuse, Former UCCE Farm Advisor Solano and Yolo Counties; and Bill Krueger, UCCE Farm Advisor Emeritus, Glenn County in the September 2011 Sacramento Valley Walnut … Continue reading
Adapted from the article “Guidelines for handling and planting bareroot walnut nursery trees” by Carolyn DeBuse, Former UCCE Farm Advisor, Solano and Yolo Counties and Bill Krueger, UCCE Farm Advisor Emeritus, Glenn County in the October 2012 Sacramento Valley Walnut … Continue reading
Adapted from the article “Guidelines for Handling Potted Walnut Clonal Rootstock Plants” Janine Hasey, UCCE Farm Advisor Sutter, Yuba, Colusa Counties in the March 2013 Sacramento Valley Walnut News Clonal Paradox rootstocks are micro-propagated in a lab and then potted … Continue reading
Adapted from the article “Site preparation for walnut planting”, by Bill Krueger UCCE Farm Advisor Emeritus, Glenn County in the August 2008 Sacramento Valley Walnut News. Preparation for planting a new walnut orchard should start with a soil evaluation. Walnuts … Continue reading
Adapted from “Soil testing and analysis: what to expect in the report” by Allan Fulton, Farm Advisor, Tehama, Glenn, Colusa, and Shasta Counties and Dirk Holstege, Director Analytical Laboratory, University of California Davis Agriculture and Natural Resources in the May … Continue reading
Adapted from the article “Planting a successful annual reseeding cover crop” by Janine Hasey, UCCE Farm Advisor, Sutter, Yuba, Colusa Counties and Mark Cady, Community Alliance with Family Farmers in the August 2008 Sacramento Valley Walnut News. Updated October 2018. … Continue reading
Adapted from the article “Irrigation Management Tools for Developing Walnut Trees” by Richard P. Buchner, UCCE Farm Advisor, Tehama County, Allan E. Fulton, UCCE Farm Advisor, Tehama, Glenn, Colusa and Shasta Counties in the July 2014 Sacramento Valley Walnut News. … Continue reading
Adapted from the article “Continue Watching for Aphid and Spider Mite Infestations” by Bill Krueger, UCCE Farm Advisor Emeritus, Glenn County in the August 2009 Sacramento Valley Walnut News. Aphids There are two aphid species that damage walnuts, the walnut … Continue reading
Adapted from the article “Managing Phytophthora in Walnuts” by Bill Krueger, UCCE Farm Advisor Emeritus, Glenn County and Greg Browne, USDA Research Plant Pathologist, UC Davis in the March 2010 Sacramento Valley Walnut News. Phytophthora crown and root rot is … Continue reading
Adapted from the articles “Spacing Walnuts for Optimum Light Interception and Production” by Bruce Lampinen, Walnut and Almond Specialist, UC Davis and Janine Hasey, UCCE Farm Advisor, Sutter, Yuba, Colusa Counties; and “Perspective on trends in orchard spacing, pruning and … Continue reading
Adapted from the article “Winter Irrigation During Drought” by Joseph H. Connell, UCCE Farm Advisor Emeritus, Butte County in the December 2008 Sacramento Valley Walnut News. We know that during the winter months walnuts can be hurt by either too … Continue reading