March 20, 2022
CASI's Jeff Mitchell was invited to meet with eight researchers of the Rothamsted Research facility in Great Britain as part of a research exchange program organized by the College of Agriculture and Environmental Sciences at the University of California, Davis along with several other campus researchers on March 17, 2022. Rothamsted Research is the longest-running agricultural research institution in the world. Its foundation dates from 1843. The exchange was hosted by the Global Exchange Office at UC Davis and involved individual presentations and follow-up discussions between UC Davis researchers and the Rothamsted Research visitors. Mitchell was asked to present a discussion on the topic of "Cooperative Extension in California" and shared several aspects of our CASI Center as well as the historical background of Cooperative Extension, the land-grant university, and the agricultural experiment station system in the United States.
March 4, 2022
Nearly 100 students in Dr. Anil Shrestha's weed science course at Fresno State University spent time in the field as part of their laboratory sessions to learn about the potential roles that cover crops and roller/crimpers might play in weed management and moreover, improved performance annual crop production paradigms. Although roller/crimpers have been around and used in several places around the world including the South American countries of Brazil, Argentina, and Paraguay, as well as in the Southeast US for decades, the technology is relatively new in California. However, Dr. Shrestha and his MS student, Robert Wilmott, have been evaluating the approach for five years on the CSU Fresno campus with good success and this spring their current study provided a very nice and rich educational opportunity for students to visit and observe.
During the week of February 28 through March 4, three lab sections of Dr. Shrestha's class toured the various cover crop mixes that he and Wilmott have in their study. The students learned about the background of the roller/crimper, its potential use in improved performance production systems that rely on principles of soil health management, and characteristics of the various cover crop treatments that Shrestha and Wilmott are evaluating as part of their ongoing study. Wilmott led each group of students out into the field where they observed the different cover crops and also learned about various weed species that were seen often in bare spots where the cover crops didn't cover the soil.
At the end of the lab, students helped Wilmott and Shrestha by collecting data on the maturity stages of two cover crops, Pacheco triticale and Merced rye, that are part of a multi-site evaluation of two maturity stages for cover crop rolling. Students took data on the percentage of random plants that were at the anthesis or initial flowering stage in the strips where replicated plantings of the two cover crop species were located. Rolling at antheis is one of the roller/crimper timing treatments that Shrestha and Wilmott and a wider group of colleagues in Salinas, Santa Cruz, and Davis are evaluating this spring.
A short video is available for viewing at You Tube describing the students' work in the field at
More background information on cover crop roller/crimpers is also available at the You Tube site
February 6, 2022
Expert weed ecologist, Dr. Anil Shrestha, of Fresno State's Department of Viticulture and Enology, has begun two exhaustive investigations of weed prevalence and diversity at the organic farm of USDA NRCS CIG Project farmer member, Phil Foster. The study involves four cover crop treatments that include Merced rye, Pacheco triticale, Phil's 'go to' mix of Phacelia, millet and faba bean, and the SJV morning glory suppression mix of Cary Crum that other CIG farmers are also trying at their farms. Each cover crop is laid out in fifteen-foot wide strips that are replicated throughout the field three times. Shrestha took his first set of data on February 3rd at the Santa Ana ranch study site and plans to return in two weeks for additional observations there as well as at Phil's San Juan ranch location where a similar replicated study is underway. Suffice it to say that ample very interesting data will stem from these monitoring efforts and that even in the initial sampling there seemed to be rather striking differences between the cover crops in terms of weed counts. A plot plan of the study that Phil prepared and a short video clip of the sampling methodology used by Dr. Shrestha are provided below. A link to a You Tube link of the video of Dr. Shrestha's sampling technique is provided here as well.
January 20, 2022
Undergraduate student, Jennifer Valdez-Herrera, took home the first prize award in this year's student poster competition of the California Weed Science Society that was held January 19th - 21st at the Hyatt Regency Hotel in Sacramento, CA. Her poster titled, Potential of roller-crimper technology for weed suppression in annual crops, reported on the first four years of a study that has been conducted on the Fresno State campus under a center pivot irrigation system. The rolled cover crops are followed by strip-tillage planted silage corn. Five mixes, rye, an ultra high diversity mix from Green Cover Seed in Bladen, NE, a multiplex mix from Lockwood Seed and Grain in Chowchilla, CA, a faba bean and Phacelia combination, and a three-way mix of rye, peas, and purple vetch are replicated three times in about 300 foot strips throughout the field. A copy of Valdez-Herrera's poster is provided below and a short 56-second video showing the current stage of growth of the 2021 - 2022 cover crops may be seen at
January 20, 2022
Year 5 of a major cover crop roller crimper study is underway on the Fresno State campus in the school's center pivot field under the monitoring supervision of Dr. Anil Shrestha and his undergraduate student research assistant, Jennifer Valdez-Herrera and graduate student, Robert Wilmott. The project repeats five cover crop mix treatments (rye, an ultra high diversity mix provided by Green Cover Seed of Bladen, NE, a Multiplex mix of Lockwood Seed and Grain in Chowchilla, CA, a two-species mix of faba bean and Phacelia, and a three-way mix of rye, peas, and purple vetch. A short, 49-second video showing Valdez-Herrera and Wilmott and the stage of growth of the cover crops on January 20, 2022 can be viewed at the You Tube link