Johnsongrass can be a tough weed to control. Ryan Hill (UCCE Tehama, Shasta, Glenn) comes on the podcast to update us on the integrated year-round management of this perennial weed in orchards. UC ANR has great resources on distinguishing Johnsongrass and other young summer grass weeds . Johnsongrass identification photos can also be found on the podcast website . ANR also has a great guide to Johnsongrass biology and management . Connect with a local UCCE weed expert! UC ANR has recently expand...
Jun 22, 2025•27 min•Ep. 277
Dr. Pat J. Brown (UC Davis) discusses exciting new clonal rootstocks being developed by a team of UC and USDA researchers. Pat is looking for growers to trial these new clones, in particular K3 an exciting new rootstock that has produced good growth, yield, and very low crown gall. You can contact Pat at [email protected] . Please also CC your local UCCE walnut farm advisor . Come to an upcoming extension meeting! In the Sacramento Valley : North Sac Valley Groundwater and SGMA is on Tuesday, ...
Jun 10, 2025•18 min•Ep. 276
Three PhD entomologists with UC Cooperative Extension: Sudan Gyawaly, Jhalendra Rijal, and Houston Wilson discuss integrated management of the leaffooted and stink bug pest complexes in California nut crops. Be sure to first listen to part I where the three experts discuss phenology and monitoring of these pest complexes. More information on controlling plant bugs in almonds and pistachios can be found on the UCIPM website; there are separate pages for stink bugs and leaffooted bugs, and in pist...
Jun 04, 2025•30 min•Ep. 275
Three PhD entomologists with UC Cooperative Extension: Sudan Gyawaly, Jhalendra Rijal, and Houston Wilson discuss the phenology and monitoring of the leaffooted and stink bug pest complexes in California nut crops. Including an exciting update from Houston Wilson (UC Riverside) on the trap and lure for leaffooted bug. Stay tuned for part two where the expert panel discusses the integrated management of these pests. More information on controlling plant bugs in almonds and pistachios can be found...
May 27, 2025•33 min•Ep. 274
Dr. Roger Baldwin (UCCE Specialist in Human-Wildlife Conflict Resolution) discusses orchard management of pocket gophers, ground squirrels, voles (meadow mice), roof rats, and deer mice. This is a compilation of two episodes from 2022, with Luke Milliron providing a new introduction with highlights from 2024/2025. Skip to the pest you’re concerned about: 00:05:35 Pocket Gophers 00:35:12 Ground Squirrels 00:48:33 Voles/Meadow Mice 01:02:38 Roof Rats 01:12:39 Deer Mice 2025 Update on Roof Rats: Th...
Apr 25, 2025•1 hr 21 min•Ep. 273
Drs. Or Sperling (ARO-Volcani) and Maciej Zwieniecki (UC Davis) discuss their groundbreaking research on almond irrigation. That research has culminated in an exciting irrigation scheduling application . We also get an overview of almond production in Israel. The UC Davis Carbohydrate Observatory is also referenced. Come to an upcoming extension meeting! Sacramento Valley San Joaquin Valley (scroll to the bottom) The views, thoughts, and opinions expressed are the speaker’s own and do not repres...
Apr 18, 2025•50 min•Ep. 272
Cytospora is a devastating fungal canker disease in California prune production. Themis Michailides (UC Davis at Kearney Ag Center) updates us on the biology and management of this important disease. Themis has covered this disease on the podcast before but is back with key updates. Come to an upcoming extension meeting! Sacramento Valley San Joaquin Valley (scroll to the bottom) The views, thoughts, and opinions expressed are the speaker’s own and do not represent the views, thoughts, and opini...
Apr 07, 2025•33 min•Ep. 271
Fire is a fact of life in California, whether you live in a fire-prone area or you live in an area that can be impacted by smoke. Smoke doesn’t just cause health issues to animals - it impacts plants, too! Jessica Orozco and Maciej Zwieniecki at UC Davis have been using citizen science data from The Carbohydrate Observatory to try to guess at the impacts on tree nut orchards in the Central Valley. Are you interested in contributing to the carbohydrate observatory? You can find out how to submit ...
Mar 04, 2025•29 min•Ep. 270
English/Persian walnuts have a fairly high chill requirement and can suffer from poor bud break and reduced yields in years with marginal or low chill accumulation. Katherine Jarvis-Shean (UCCE Yolo, Solano, and Sacramento Counties) has been looking at the efficacy of rest-breaking agents, both in semi-controlled conditions and in commercial orchards. She shares how well they work, their effect on yields, budbreak, and walnut quality, and the surprising interaction of chill accumulation with res...
Feb 19, 2025•35 min•Ep. 269
Nonstructural carbohydrates are the energy storage compound of trees. They are built from simpler sugars that are created via photosynthesis, and the synthesis of starch from these sugars and the breakdown of starch back into simple sugars is a dynamic relationship that is involved in, or may even signal, the transition from dormancy into bloom. Guests Maciej Zwieniecki and Katherine Jarvis-Shean also discuss why dormancy breaking agents work, the tastiness of starch vs sugar, and more! Come to ...
Feb 12, 2025•47 min•Ep. 268
Sam Sandovol Solis, professor of cooperative extension in water management at UC Davis, pulls out the crystal ball for the fourth time to predict what the 2024-2025 water season will end up looking like. Sam and podcast host Phoebe also discuss water management in a future with uncertain supplies, and what growers can do in the present to maximize soil water, and how to think about water availability in the long term. Sam mentioned a map that shows groundwater recharge suitability, you can find ...
Feb 07, 2025•27 min•Ep. 267
Almonds and pistachios are native to arid climates and are drought tolerant tree species. In California however, the high cost of production and land value pushes growers to maximize yields, which means trying to meet the full evaporative demand (though many growers apply much less water than this!) This is not the strategy everywhere, however, even in other areas that also have high production costs. In this episode, Phoebe discusses almond production in the Iberian Penninsula with Sebastian Sa...
Jan 29, 2025•1 hr 15 min•Ep. 266
At a time when California orchard farmers are being challenged by poor economics and tightening regulations – coming irrigation advances promise labor and time savings. I speak with Tom Devol (retired Almond Board of California) to discuss the past, present, and future of California orchard irrigation. Come to an upcoming extension meeting! Sacramento Valley San Joaquin Valley (scroll to the bottom) The views, thoughts, and opinions expressed are the speaker’s own and do not represent the views,...
Dec 28, 2024•29 min•Ep. 265
Phellinus heart rot in prune trees destroys structural integrity. Laurel Hoffman (UC Davis) updates us on the biology and management of this important disease. Come to an upcoming extension meeting! Sacramento Valley San Joaquin Valley (scroll to the bottom) The views, thoughts, and opinions expressed are the speaker’s own and do not represent the views, thoughts, and opinions of the University of California. The material and information presented here is for general information purposes only. T...
Dec 16, 2024•30 min•Ep. 264
We posted this episode back in 2020 and are pulling it out of the archives. It’s an interesting story of the surprising resilience of a tree after wildfire events that are unfortunately too common. Come to an upcoming extension meeting! Sacramento Valley San Joaquin Valley (scroll to the bottom) The views, thoughts, and opinions expressed are the speaker’s own and do not represent the views, thoughts, and opinions of the University of California. The material and information presented here is fo...
Nov 26, 2024•17 min•Ep. 263
Sudden autumn freeze events still sneak up on California walnut growers – as they did to some growers last Halloween (2023). Clarissa Reyes (UCCE Sutter-Yuba) and Luke Milliron (UCCE Butte) discuss the steps to prepare for freeze in walnut. At the time of posting – there was patchy frost on the morning of 11/18/24 and predicted also for 11/19/24. Thankfully, there is surface soil moisture in orchards from recent rains and the temperature decline to freezing temps has been gradually taking place ...
Nov 18, 2024•22 min•Ep. 262
It’s been a year since Carpophilus truncatus (Carpophilus beetle) was found in California. Jhalendra shares some research updates and observations with host Phoebe Gordon. Come to an upcoming extension meeting! Sacramento Valley San Joaquin Valley (scroll to the bottom) Mention of an agrichemical does not constitute a recommendation, merely the sharing of research findings. Always follow the label. The label is law. Find out more at ipm.ucanr.edu . The views, thoughts, and opinions expressed are...
Nov 12, 2024•27 min•Ep. 261
Luke Milliron, Phoebe Gordon, and Roger Duncan discuss the three almond variety trials 10 years after they were planted across the Central Valley. Thanks to our grower cooperators and to the Almond Board of California for funding these trials. You can find more about the results discussed in our 2023 report . Details discussed can also be found in an upcoming fall/winter issue of West Coast Nut. Come to an upcoming extension meeting! Sacramento Valley San Joaquin Valley (scroll to the bottom) Th...
Oct 28, 2024•39 min•Ep. 260
Pistachios alternate bear, which changes the dynamics of nitrogen uptake and allocation within the tree on a year to year basis. To add to this, the newer cultivars, Golden Hills and Lost Hills, alternate bear less than Kerman, especially when they are planted on the high vigor UCBI. Doug Amaral (UCCE Kings County) decided it was time for an update on the nitrogen demand curves, and we discuss what he’s found in this episode. Come to an upcoming extension meeting! Sacramento Valley San Joaquin V...
Oct 15, 2024•12 min•Ep. 259
A Third Thursday x Growing the Valley collab! Karla Caldera (CSUC graduate student) discusses the research she is conducting at the walnut variety trial located at the Chico State University Farm (2:27) and Dr. Pat J. Brown talks and answers grower questions about the Walnut Improvement Program at UC Davis that aims to bring improved plant material to the walnut industry (9:50). Check SVO for future Third Thursdays: Things from the Field events, and a brief article on the walnut variety trial . ...
Oct 10, 2024•55 min•Ep. 258
Trying to predict when trees will come out of dormancy and whether they’ve stayed in dormancy for a long enough period of time is a very old science. The methods for calculating chill has changed, but the measurement method, measuring air temperatures, has not. Giulia Marino, Professor of Cooperative Extension at UC Davis, measured the bark temperature of cherry trees in a recent research project. You can probably predict what she found, but how different the temperatures are will surprise you! ...
Oct 01, 2024
Phoebe breaks down the importance and best practices surrounding potassium nutrition in orchard crops. Phoebe and Franz Niederholzer wrote an excellent article on K nutrition CDFA – FREP Fertilization Guidelines Sign up for the 2024 Pistachio Short Course here : Thank you to the Almond, Pistachio, Prune, and Walnut Boards of California for their kind donations. Thank you to Muriel Gordon for the music. The views, thoughts, and opinions expressed are the speaker’s own and do not represent the vie...
Sep 24, 2024•15 min•Ep. 256
Measuring plant water status is a critical but underused tool in irrigation management. It allows us to determine whether plants actually need water, but is time consuming, done during the hottest portion of the day, and difficult to do at a large scale. Commercial devices to measure plant water status are a fairly recent addition to the agricultural tech field, but are they accurate? Isaya Kisekka, a professor of water management at UC Davis, has been evaluating them in almonds and shares what ...
Sep 17, 2024•27 min•Ep. 255
Jaime Ott discusses the resurgence of prune brownline in the northern Sacramento Valley. In addition to prune, Jaime reminds us to be on the lookout for symptoms of Tomato ringspot virus in almond, peach, and cherry. Also caused by Tomato ringspot virus: Learn about Yellow Bud Mosaic in almond and peaches Learn about Cherry Stem Pitting Come to an upcoming extension meeting! Sacramento Valley San Joaquin Valley (scroll to the bottom) The views, thoughts, and opinions expressed are the speaker’s ...
Jul 02, 2024•17 min•Ep. 254
Houston Wilson, Professor of Cooperative Extension in entomology with UC Riverside, gives us our semi-yearly update on Sterile Insect Technique (SIT) work in Navel Orangeworm, through work completed in 2024. It’s a long (20 year or so) long road, but may provide an additional tool in the IPM toolbox for controlling navel orangeworm. Listen to find out more! Come to an upcoming extension meeting! Sacramento Valley San Joaquin Valley (scroll to the bottom) Mention of an agrichemical does not const...
Jun 26, 2024•Ep. 253
Incorporating large amounts of woody biomass into soil, such as in whole orchard recycling (WOR), can promote carbon sequestration, nutrient recycling, and ecosystem health in agricultural fields. Yet uncertainty regarding the effects of WOR on soil carbon and nitrogen dynamics influences management decisions. Recently, Mae Culumber, Ph.D. with UC Cooperative Extension, Suduan Gao, Ph.D. with the USDA Agricultural Research Service, and others performed research to evaluate the effects of woodchi...
Jun 04, 2024•14 min•Ep. 252
Soil health is broad term that encompasses a important topic: functional soil that can support human activities, animals, and plants. Measuring soil health can be difficult even for soil scientists, but in today’s episode, Sarah Light shares some tools that growers, PCAs, and CCAs can use to judge soil health in their or their clients’ orchards. Thank you to the Almond, Pistachio, Prune, and Walnut Boards of California for their kind donations. Thank you to Muriel Gordon for the music. The views...
May 28, 2024•16 min•Ep. 251
In 2023 UCANR advisors and specialists got an unusual number of farm calls on branch cankers in almonds, many of which turned out to be aerial phytophthora. Florent Trouillas with UC Davis goes over the pathogen, its lifecycle, and the conditions in 2023 that led to this outbreak. Come to an upcoming extension meeting! Sacramento Valley San Joaquin Valley (scroll to the bottom) Mention of an agrichemical does not constitute a recommendation, merely the sharing of research findings. Always follow...
May 21, 2024•21 min•Ep. 250
Luke Milliron discusses the growing list of problems with the Monterey almond variety in the northern Sacramento Valley. Leafing failure (what is it) Leafing failure (what might be causing it) Flowering failure Come to an upcoming extension meeting! Sacramento Valley San Joaquin Valley (scroll to the bottom) The views, thoughts, and opinions expressed are the speaker’s own and do not represent the views, thoughts, and opinions of the University of California. The material and information present...
May 14, 2024•22 min•Ep. 249
This week, we share an episode that was TWO YEARS IN THE MAKING (if you count continually rescheduling episode recording sessions due to various conflicts and then forgetting about it for a year as making an episode). Phoebe interviews Amisha Poret-Peterson with the USDA-ARS on the basics of soil microbiology. We discuss the complexity and role of the soil microbiome, bulk soil vs the rhizosphere, and more! Listen to hear some very amazing things. Come to an upcoming extension meeting! Sacrament...
Apr 16, 2024•31 min•Ep. 248
