Harvester Race?

At the USA Rice Outlook Conference an interesting report was given by Texas researchers. They termed their experiment a “harvester race”. The question they raised was—what effect does speed have on the amount of grain going into the harvester tank. Since our bent in California seems to be to harvest faster and faster, this sounded like a relevant topic.

The test was set up in such a way to allow each of the three test harvesters to reap exactly the same number of feet in the field. Each harvester had a factory representative there to optimize the harvester characteristics. All three of the harvesters had a few hundred hours on them so they would be broken in. All tests were replicated and the harvester teams audited the driving of the others just to keep everything above board. The harvested field had green straw and was muddy.

Harvested grain in the tank was weighed after each test. The straw choppers were turned off and the rice coming out the back was caught in pans. It was interesting that when the straw choppers were turned on the researchers had trouble finding the grain that was coming out with the straw. Keep that in the back of your mind as you read the results, especially if you construct your own test.

The results in table 1 show the average of the three harvesters because the dramatic result is in the speed data. All results are normalized for 12% moisture. Stubble height averaged 17 inches ±0.8 inches cut by a 25 foot header. The term MOG stands for “material on the ground” or as they say in Texas, “Money on the ground”.

I think the results are quite clear. It pays to go slow.

Leaf Color Chart

For the past several years Cass Mutters has been working on an easy method of determining the nitrogen level in a rice crop. His work has now produced a Leaf Color Chart that is easy to use.

The leaf color chart was developed by planting several different rice varieties in test plots and using seven different levels of nitrogen on each variety. Plant leaves were sampled three times between mid-tillering and panicle initiation. Thirty leaf samples from each variety and fertilizer treatment were taken for color analysis with a colorimeter. Using a sophisticated technique of quantifying the color value, a distinct leaf color that corresponds to the different levels of tissue N was established. These precise colors were sent to a fabricator and formed into acrylic plates. You can see the eight distinct color plates in the picture. Each of these plates corresponds to a different level of nitrogen.

You may use the chart as either a whole field tool or with a single leaf. For whole field analysis, it is designed in such a way that you can tilt it slightly and look over the top where you will see only the color plates and the field before you. This method should be used only with the sun to your back between 9 a.m. and 3 p.m. To analyze a single leaf, you can pick the Y leaf (most recently matured) and lay it across the plates. Repeating this process with at least 10 leaves will give an average color value for the field.

Also contained with the chart is a calibration table for the different classes (medium, short, Japanese) of rice. Finally, a nitrogen assessment chart is included to help determine if the rice has the right amount of leaf nitrogen at the present plant growth stage.

This tool represents a very economical and durable alternative to the chlorophyll meter. It is made of a heat resistant plastic to withstand the rigors of a truck dashboard. No batteries are required. You can even drop it in a check without damage. Leaf Color Charts can be purchased from the Rice Research Board office for $25 and will also be available at the CE Winter Rice meetings. Why $25 you ask? That amount helps to defer the cost of injection molding and producing the chart. Make checks payable to the Rice Research Board.

Bob Herkert

Longtime California rice industry advocate Robert E. “Bob” Herkert died unexpectedly at his home on December 19, 2000, reportedly succumbing to heart failure. He was 42. California rice industry leaders responded with shock and sadness.

“Bob was a truly gifted and creative individual who gave everything he did 100 percent of his time and energy,” said Tim Johnson, president and chief executive officer of the California Rice Commission

Herkert had worked for the rice industry for more than a decade, also serving as a staff member of the California Rice Industry Association and California Rice Promotion Board. He was instrumental in forming the California Rice Commission in 1999.

Colleagues described Herkert as an untiring advocate for rice farmers and the rice industry. He was perhaps best known for his work promoting the positive environmental traits of rice farming, especially the benefits to waterfowl and wildlife, such as creation of habitat and food.

In 1999, Herkert was honored for his part in writing and producing an award-winning video about the relationship between rice farming and wildlife habitat.

This year, Herkert successfully led efforts to pass a new law, The Rice Straw Alternatives Act of 2000, aimed at creating alternative uses for rice straw. The new law allocated $2 million to help find new ways to use rice straw.

Friends described Herkert as an expressive, outgoing and friendly man who loved to tell jokes and stories. He lived in Colusa where he enjoyed hunting, riding horses and serving as a member of the Colusa County Sheriff’s Posse.

Herkert is survived by his wife, Audra, son, Hans, and daughter, Hanna.

A trust fund has been set up for the benefit of the family. Gifts should be sent to: Bob Herkert Memorial Fund, c/o Wells Fargo Bank, 501 Market Street, Colusa, CA 95932.

Propanil Progress

In past issues I have written about the progress of propanil research. A second year of testing was conducted in 2000 and this report will summarize the work and findings.

As a quick review, members of the rice industry and the propanil registrants formed the California Propanil Task Force in late 1998 to seek ways to allow for greater usage of propanil while maintaining safety for sensitive crops. The group had objectives to decrease ground buffers, increase daily usage, and allow aerial applications; the RRB conducted research toward these goals. This group worked with DPR to establish acceptable research protocols. Extensive research was performed in 1999, the results analyzed and recommendations made.

At the end of the first year, there were still a few areas that were not clear. A second year of testing was proposed, prepared and executed. Again, during this second year, a great effort was put forth by RRB researchers Sara Goldman-Smith and Bill Steinke to conduct the research in a manner that would be valid and acceptable to DPR.

During September and October of 2000, the Task Force met often to bring together reams of information recently returned from the lab. Members spent many hours analyzing the data to distill it down to sensible recommendations and meet DPR’s time constraints for 2001 regulatory changes. Finally on November 1, 2000 the Task Force presented its recommendations to the California Rice Commission (see “Propanil recommendations” sidebar). These proposals were cautiously crafted for the greatest acceptance by DPR, retaining the production tool and keeping our neighbors happy.

The Rice Commission is well equipped to interface with DPR’s regulatory process with their Section 18 experience, and they requested the lead role in this phase of the project. Thus, responsibility to interface with DPR was transferred to them. Bob Hedrick crafted the appropriate language in late November for the regulatory changes and is working with DPR to bring about these changes. The process is a long and complicated one, so there is no firm date when the negotiations with DPR will be complete.

Task Force members stand ready to assist DPR or CRC as needed. If additional studies are called for, RRB, CRC, or the registrants will handle the research work.

Chairman George Sligar extends his congratulations to the Task Force on a job well done. The work has been intense and the effort very great, but the sun is now setting on the Task Force and their work is complete. The Chairman extends his thanks to the organizations that cooperated so well together: UC Davis, Cooperative Extension, CAAA, Agricultural Commissioners, DPR, Rohm-Haas, RiceCo, many rice growers, CRC and the RRB.

New RWW Trap

With the loss of Furadan growers have little choice but to switch to post-flood insecticide treatments for Rice Water Weevil. The difficulty with these materials is their need for precise timing to be most effective since their residual activity is limited. To address this need for precise timing, our UC entomologist Larry Godfrey, has been experimenting with an in-field floating RWW trap to monitor pest populations.

Godfrey did a wide area monitoring project in 2000 that showed wide variations in RWW levels over different locations. This confirms grower comments that some individual fields will have weevils, while other nearby fields do not. Individual field monitoring would allow you to find out when the RWW arrives and how many weevils are present.

In California, by the time the adult leaf scarring threshold is met (~20%), it will in all likelihood be too late to apply Dimilin or Warrior (i.e., the eggs have already been deposited). Therefore, the need for a new sampling tool. The University of Arkansas has developed a floating trap that appears to have merit in their system. The goal of the RRB study was to evaluate the utility of this trap in the California water-seeded rice system. The capacity to capture RWW adults was the first criterion and the relevance of these data for predicting subsequent larval populations was the second point.

Studies were conducted in six grower fields in Colusa, Butte and Sutter counties. Traps were placed in the fields after seeding but before rice emergence and were anchored about 5 feet from the levees. Fields were not treated for RWW. RWW adults were collected from the traps 3 times per week. The number of RWW larvae was determined with the standard core samples in mid-late June and again in early-mid-July.

Adult RWW were captured at five of the six locations. Peak populations were approximately 3.5 adults per trap per day; however, most levels were less than 1 adult per trap per day. The Arkansas designed trap appeared to effectively capture RWW adults. Algae and field draining were problematic for trap operations. Larval populations peaked at ~13 per core sample with most levels being in the 0 to 4 range. Most importantly, there was a relationship between the number of adults captured and the resulting larval populations. More data needs to be collected, especially at higher RWW pressures, to strengthen the relationship. Ultimately, additional research should produce an adult threshold value to assist in timing applications of Dimilin or Warrior.