Author Archives: Katherine Jarvis-Shean

What new research into carbohydrates is teaching us about California orchards

Orchards up and down the Central Valley sit bare and leafless during winter. But just because we can’t see active growth with our eyes, doesn’t mean the trees themselves aren’t active. Recent years of research by the Zwieniecki lab (the Z Lab) at UC Davis, including the Carbohydrate Observatory, have been shedding light on what is happening in orchard trees during their yearly cycles, including during this dormant period. This research has been used to better explain how trees may be counting winter chill and spring heat. Continue reading

Ethephon in a Straggled Leaf-Out, Lean Price Year

Given this spring’s prolonged leaf-out window, it is likely that there will also be a wide window in the timing of hull split and a need for two shakes in some varieties. Ethephon is a commonly used tool for advancing hull split and harvest-readiness in walnuts. Remember that there are two potential timings of ethephon, based on different goals. Continue reading

Rootstock Trial for Boron Tolerance – 2019 Update

Excessive boron in soil or irrigation water is not widespread in the Central Valley, but where present, it can be a substantial obstacle to almond production. A rootstock trial in Yolo County was designed to find which almond rootstocks do better or worse under high boron conditions. What follows is a summary of findings to date. What follows is a summary of findings to date. Continue reading

Cover Crop Seed Selection

There are plenty of benefits that can come from cover cropping in an almond orchard, including improved orchard access, improved water infiltration, encouraging native pollinizers and improved honeybee health. But all the options of species to plant can be overwhelming. Herein we’ll review how to pick a cover crop seed blend for a particular orchard. Continue reading