Your source for orchard news & information in the Sacramento Valley
Jaime Ott, UCCE Tehama, Shasta Glenn, Butte Counties Given the early bloom and leaf-out of our walnuts this year, spring rain will put us at risk of blight. At the time of writing, we are already past catkin expansion and … Continue reading
Crown rot and root rot caused by Phytophthora species are diseases of great concern for walnut growers. Many people believe that irrigating with surface water puts your trees at risk of Phytophthora, and that irrigating with groundwater is the best way to prevent these diseases. However, a recent study of Phytophthora in irrigation water and orchard soils tells a different story. Continue reading
Jaime Ott, UC Extension Tehama, Shasta, Glenn, and Butte Counties This work was partially funded by the Stockton East Water District Crown rot and root rot caused by Phytophthora species are diseases of great concern for almond growers. Many people … Continue reading
Jaime Ott, UCCE Tehama, Shasta, Glenn, and Butte Counties Though our weather outlook for the next couple of months is leaning toward warmer weather than usual, a cold snap during bloom and leaf-out could cause significant bacterial blast damage. Make … Continue reading
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 … Continue reading
Jaime Ott, UCCE Tehama, Shasta, Glenn, and Butte Counties The growing degree hours in the 30 days after full bloom (GDH30) is a measurement which predicts reference date, harvest date, and fruit sizing potential. It is counterintuitive, but higher GDH30 … Continue reading
Jaime Ott, UCCE Farm Advisor, Tehama, Shasta, Glenn, and Butte Counties According to Dr. Jim Adaskaveg, UC Riverside professor who has been studying walnut blight for decades, these are the most common mistakes growers make in their blight control program: … Continue reading
Jaime Ott, UCCE Tehama, Glenn, Shasta, Butte Luke Milliron, UCCE Butte, Glenn, Tehama Infection by Cytospora and other fungi is a major cause of scaffold and tree loss in prunes, resulting in reduced yield. These fungi can also infect young … Continue reading
Jaime Ott, UCCE Tehama, Shasta, Glenn, and Butte Counties With walnut prices modestly up, this is a good time to look at your orchard operation, grade sheets, and pest/disease challenges in the last few years and make a plan for … Continue reading
North Sac Valley: Jaime Ott, UCCE Tehama, Shasta, Glenn, Butte Counties Despite a much earlier bloom than last year, harvest started only a few days earlier. Fruit size and sugar at harvest was variable: blocks with heavy cropload or which … Continue reading
Jaime Ott, UCCE Tehama, Shasta, Glenn, and Butte Counties Since this spring (2023), we have found prune brownline disease (brownline) in three Sac Valley orchards on Krymsk 86 rootstock. Symptoms include tree decline and rapid collapse of the entire canopy. … Continue reading
Pseudomonas syringae pv. syringae is ubiquitous in orchards, so bacterial blast can develop whenever environmental conditions are right (freezing or near-freezing and wet). While copper sprays have been used to protect trees from bacterial blast, resistance is common in P. syringae populations throughout the state. Unfortunately, it is no longer effective for controlling bacterial blast in some orchards, however, Kasumin® 2L has been shown to be effective. Continue reading
In 2023, the cold, wet weather during bloom and leaf-out resulted in bacterial blast damage in many Sacramento Valley almond orchards. If conditions this year are cold and wet during bloom, we may see a recurrence of blast: make a plan now to keep blast damage to a minimum. Continue reading
If you haven’t already, look at your orchard operation: take some time to Stop, Think, Observe, and Plan. Read for an overview on resources on topics on spray calibration, sanitation, codling moth mating disruption, pests, and more. Continue reading
Excessive water, caused by rain, flooding, or even overirrigation, is a challenge for orchards and can cause two very different problems: waterlogging and Phytophthora infection. Given that we had bountiful rain this winter and orchards with standing water were common, continuous monitoring and collaboration with your PCA or farm advisor will be increasingly valuable. Continue reading