The annual UC Davis Small Grains and Alfalfa Field Day will take place on Thursday, May 17, 2017 at the Agronomy Field Headquarters (2400 Hutchison Drive, Davis, CA 95616). Registration opens at 7:30am, and lunch is provided between the small grains morning program and alfalfa afternoon program. The event is free and open to the public, and continuing education credits will be available. Directions are as follows: 

The field day is located on Hutchison Drive, just west of Davis. Take the Hwy. 113 exit north from I-80, or Hwy. 113 south from Woodland. Exit west on Hutchison Drive. Take a right at the first roundabout, a left at the second roundabout, and the Agronomy Headquarters is about ¼ mile down in a clump of trees and buildings on the left. 

The agenda is as follows:

8:00am – Noon: Small Grains Program

8:00     Welcome and Introductions—Mark Lundy, UC Davis

8:05     Plant Sciences Future Developments—Gail Taylor, UC Davis

8:10     California Wheat Commission remarks—Claudia Carter, California Wheat Commission

8:15     California Crop Improvement Association remarks—John Palmer, CA Crop Improvement Association

8:45 – 11:50 Field Tour

8:45     New wheat varieties with increased resistant starch—Jorge Dubcovsky, UC Davis

8:55     New wheat releases “Central Red” and “Desert Gold”—Jorge Dubcovsky, UC Davis

9:00     Improving barley malting varieties and oats—Alicia del Blanco, UC Davis

9:10     Organic wheat breeding and naked barleys—Allison Krill-Brown, UC Davis

9:20     Improving triticale for bread and forage—Josh Hegarty, UC Davis

9:30     Genetic regulation of wheat grain number—Sarah Kuzay, UC Davis

9:40     Genetic regulation of grain size and its effects on quality—Alejandra Alvarez, UC Davis

10:10   Nitrogen management in malting barley—Taylor Nelsen, UC Davis

10:20   Herbicide management demonstration trial in wheat—Mariano Galla, UCCE

10:30   Strategies for reducing mice damage in SDI systems during small grain crop rotations— Konrad Mathesius, UCCE

10:40 Updates on statewide small grain research and extension efforts, with comments on variety performance, pests and diseases, nitrogen management, and extension tools— Mark Lundy and Nicholas George, UCCE/UC Davis

11:05   New wheat entries in Regional trials—Oswaldo Chicaiza, UC Davis

11:15 Comments from breeders with entries in UC Regional trials

11:30   Trial observations

12:00 Barbeque Lunch: Many thanks to California Crop Improvement Association for the complementary lunch!

12:30 – 4:30: Alfalfa and Forage Program

12:30   Welcome and Introductions—Dan Putnam, UC Davis

12:45   Statewide Nitrogen Management Survey—Jessica Rudnick, UC Davis

1:00     Field Tour:

1:00     Overhead Sprinkler Studies with alfalfa & corn at UC Davis—Isaya Kisekka, UC Davis

1:15     Managing Water for Drought and Salinity: --Michelle Leinfelder-Miles, UCCE

1:30     Estimating the P and K Requirements of Alfalfa—Daniel Geisseler, UC Davis

1:45     Alfalfa Weevil Studies and IPM Approaches to Weevil Control—Rachael Long, UCCE

2:00     Kura Clover and Switchgrass Studies – Dan Putnam, UC Davis

2:05     Reduced Lignin Alfalfa Interactions with Harvest Scheduling – Brenda Perez,UC Davis

2:20     Seedling Weed Management in Alfalfa – Mariano Galla, UCCE

2:35     Fun with Drones, Sensors and Measurements:  Monitoring Alfalfa for Growth, Pests,and Water Use—Umair Gull, UC Davis

2:50     Producing Protein from Alfalfa for Human Consumption: Why Alfalfa is a potential ‘engine' of world protein production – Dan Putnam, UC Davis

3:00     Breeding Tall Fescue for Quality and Summer Dormancy and Objectives of the UC Davis Alfalfa Breeding Program– Charlie Brummer, UC Davis.

3:15     What is the Interaction between Irrigation Deficits and Varieties? James Radawich, UC Davis

3:30     The Importance of Owls and Birds for Alfalfa Pest Management—Sara Kross, CSU Sacramento

3:45     An IPM Approach to gopher management in Alfalfa – Roger Baldwin,UC Davis

4:00     Weed Identification Contest – Test your Weed IQ! – Lynn Sosnoskie, UCCE

4:15     Choosing Alfalfa Varieties for Maximizing Pest Resistance and Yield—Importanceof Multiple Year Trials and Pest Ratings —Dan Putnam, UC Davis

This year, with the help of Dow AgroSciences, UC farm advisors will increase the number of armyworm traps that they will monitor in rice fields. The idea is to give growers and PCAs more localized information so that they can have a better idea of what's going on near them, and when to increase their monitoring efforts. Weekly trapping numbers will be posted on the UC Rice Online website, http://rice.ucanr.edu/armyworm_traps/.

Luis Espino will be sending a weekly “armyworm alert” email once the trap numbers are updated on the website. The e-mail will go out to those who are subscribed to one of our electronic newsletters (Rice Briefs, Rice Leaf, or Field Notes). If you receive the armyworm email but are not interested, just click on the unsubscribe link at the bottom of the email. For those who do not receive our newsletters electronically, you can subscribe to the alert email in the armyworm website: http://rice.ucanr.edu/armyworm_traps/.

I will also keep you updated through this blog, specifically on Delta trap counts.

I have received a couple inquiries from Pest Control Advisors about wheat that is showing leaf tip yellowing and burning (Fig. 1). Their suspicion is frost injury, and with the weather we have experienced over the last several weeks, their suspicion is likely true. 

Fig. 1. Yellowing and tip burning of wheat from frost injury. (Photo courtesy of PCA.)

There isn't a hard-fast rule of when frost injury will occur because several factors influence its occurrence and severity. The factors include the temperature but also the duration of cold exposure, the plant growth stage, and the growing conditions. The UC Small Grains Production Manual (see page 101) states that injury may occur with temperatures at or below 35⁰F and that even just a couple hours of exposure is enough to cause injury.

Below (Fig. 2), I present temperature data from the last month from a few local CIMIS stations. Remember that in early-February, daytime highs were getting above 70⁰F. By mid-February, however, minimum temperatures were low enough to cause frost injury, and hourly data (which I am not showing but is available from the CIMIS website) shows that temperatures below 30⁰F often spanned several hours over many nights in late-February.

The plant stage of development is critically important to how a crop may be injured from frost and how it may overcome injury. At tillering, leaf yellowing and tip burning will be the obvious symptoms. At this stage, however, yield impact will likely be slight, if any. That is because the growing point of the tillers is close to the soil and protected from the cold. When warmer weather resumes, the plants may be able to continue tillering, particularly in thin stands where there is space to fill, and overcome the injury. In the jointing stages, in addition to the leaf yellowing and tip burning, some leaf or stem lesions may be apparent. There could be moderate impacts on yield if the growing points of the tillers have been injured. Look for a chlorotic or dead leaf in the whorl. Also, try splitting the stem with a razor blade at the growing point. This picture from Texas A&M University shows how to do this. If the growing point (at the arrow) appears white, brown, or water-soaked, then there has been frost injury. Once the crop gets into the reproductive stages of growth, it becomes more sensitive to injury with bigger repercussions for yield, but luckily, I think most of the fields in our region aren't yet to these later stages of development.

Fig. 2 Recent temperature data from three San Joaquin County CIMIS stations

Keep in mind that there are field and other growth conditions that may lessen or worsen the severity of frost. Low parts of the field where cold air settles will likely show more injury. Fields that were planted earlier in the fall, or earlier-maturing varieties, that are in a later stage of growth will likely show more injury. Crops that have had good moisture and nutrient conditions may also show more injury. With one of the inquiries I received, the field had been fertilized about a month ago, and given the warm daytime temperatures we had at that time, those plants were likely resuming growth and probably got hit by the frost all-the-more. Crops that have been moisture stressed, however, may have been hardened and not show as much injury.

So, what now? Again, growers and consultants with crops in the jointing stages who are seeing leaf tip yellowing may wish to split some stems to observe whether there has been injury to the growing points. If this has occurred, there is nothing that can be done to “save” those tillers, but it might provide some insight into potential yield impact. If stem lesions appear, be on the look-out for disease infections but also lodging later in the season. Unfortunately, the most telling symptom will appear after heading when grain doesn't fill. Don't hesitate to reach out to me or your local farm advisor if you have questions about frost injury.

On Friday, January 12th, I hosted the annual SJC and Delta Field Crops Meeting in Stockton, CA. The presentations from that meeting have now been posted to my website and are available here. Also available from my website are full reports of local research trials, including the Delta sorghum seeding rate trial and field corn variety trial.

UC statewide specialists make their research results available through the Agronomy Research and Information Center (RIC) website. At the meeting, we had a presentation that referenced the small grains variety selection tool, which was developed using trial data from across the state. 

We hope you will find this information useful, and we hope you will share your feedback with us so that we may best serve your interests for research and outreach.