Sac Valley Orchards

Franz Niederholzer, UCCE Farm Advisor, Colusa and Sutter/Yuba Counties Bad bloom weather – extreme heat, cold, or extended wet weather – can drastically reduce or eliminate commercial prune crops in the Sacramento Valley. Such bloom weather is a major economic stress to growers and costs California packers market share internationally, further impacting prune economics in this state.  What’s ...

North Sac Valley: Jaime Ott, Orchard Advisor, UCCE Tehama, Shasta, Glenn, Butte Counties This year, full bloom in the northern Sacramento Valley was around March 23-25. Though we had average chilling this winter (72 chill portions by March 1st at the Gerber South CIMIS station), the weather heated up during bloom, with daily maximum temperatures around 85oF ...

The 2025 walnut pre-emergent herbicide demonstration trial is completed, and the results show strengths and weaknesses of 19 different herbicide treatments, applied either in February or March. 

Florent Trouillas, Associate Professor of Cooperative Extension, Plant Pathology, UC Davis Luke Milliron, UCCE Farm Advisor, Butte, Glenn, and Tehama Counties Red leaf blotch (RLB), caused by the fungal pathogen Polystigma amygdalinum, which was first detected in California in the spring of 2024 has found its way to the Sacramento Valley. This summer the disease was confirmed in ...

Luke Milliron, UCCE Farm Advisor, Butte, Glenn and Tehama Counties Roger Duncan, UCCE Farm Advisor Emeritus, Stanislaus County Photo: A 13th leaf Nonpareil on Krymsk 86 infected by Armillaria mellea (oak root fungus, ORF). The photo was taken by Roger Duncan in 2020 and the tree is still alive as of 2025 (18th leaf). If you have an orchard ...