By Bruce Linquist
In 2015, the University of California Cooperative Extension kicked off a yield contest with rice growers. The purpose was to provide an opportunity for rice producers and UC scientists to share information about intensive rice production in California and to recognize individuals who have achieved the highest yields.
This season, Richter AG of Colusa won with 126.9 cwt adjusted to 14 percent moisture from a field in Butte County.
Joe Richter, one of the partners in the family-owned operation, says he decided to enter the contest to see how much they could push the rice plants and still maintain quality.
“I’m on the California Rice Research board, and I’m extremely interested in figuring out how to do things better,” he says. “When Bruce brought up the idea of the yield contest at one of the research board meetings, I was all for it.”
The contest is modeled after the National Corn Yield Contest with some modifications. The rice contest required a minimum field size of 20 acres within which a 10-acre contiguous rectangular portion was selected by the grower as the contest plot.
From the contest plot, a minimum of 3 acres was harvested with the combine skipping three passes between each harvest pass. This ensured that the contest plot was adequately sub-sampled and left enough harvestable area in case a retest was required.
UC Cooperative Extension supervisors monitored the whole test to ensure combines, bank-out wagons and trailers were empty before harvesting the test plot. In addition, they measured the harvest area with tapes and measuring wheels. The supervisors went with the trailer to a certified drier where the rice was weighed and moisture taken.
Yields — adjusted to 14 percent moisture — were determined based on these measurements. If yields exceeded 120 cwt, a recheck was done. Final yields also accounted for dockage but not shrink.
In 2015, we conducted a pilot study that was restricted to Butte County. The purpose was to see if the contest could be conducted without interfering with harvest operations or the flow of traffic at the driers.
Participating growers had to have the area around the contest plot harvested before the arrival of the supervisors. Richter says participating in the contest really didn’t slow harvest – it just took a bit more coordination.
On average, growers harvested close to 3.5 acres of rice, which came close to filling up a set of double trailers. He says he selected the contest entry site in the field based on prior years’ experience.
“We have yield monitors on all of our harvester, so we analyze the data,” he says. “We know with most fields there are always high-producing areas and low-producing areas. I think this field is normally in our top 20 or 25 percent.”
Participating growers were asked to provide some mandatory information while other information on management was optional. In 2015, growers provided all the requested information, which related to water, nutrient and pest management, variety, combine and header type.
All entries were high yielders
Five entries were submitted in 2015, which Linquist says was ideal for a pilot study. Contest plots included the medium-grain M-206 and M-205 varieties. Yields were high and ranged from 108.3 to 126.9 cwt.
Richter AG’s winning entry, which involved M-205, was 126.9 cwt with a milling yield of 66/73. Results suggest that even with very high yields, milling quality is still good, Linquist says.
The yield and quality even surprised Richter.
“This was definitely higher than what I was expecting,” he says. “But it was a really good year and for us, it was a record breaking year across all of our acres.”
Richter says they didn’t treat the contest field any differently than any of their other fields. Total N rate was 167 pounds per acre. Most of this was applied before flooding the field for planting. They applied a starter blend that contained N and P about a month after planting flown into the standing water and a top dress around panicle initiation.
About 70 to 80 percent of their fields receive the same fertility programs, Richter says. The other fields may receive added potassium or phosphorus, based on soil types.
In 2016, Linquist says he’d like to expand the contest to the entire Sacramento Valley. “We’re discussing how we might divide up the area into regions with similar yield potential so that growers can compete on a level playing field,” he says.
Prizes will be given out by UC Cooperative Extension to the top two 2015 contestants. These are not large prizes – a high-quality hunting knife and a specially designed hat.
The National Corn Yield Contest winners receive larger prizes but these are given out by industry sponsors and not the contest organizer. In the future, it may be possible for companies to sponsor prizes to encourage rice yield contest participation.
Linquist says it is too early to say what Extension specialist and researchers can learn from such tests; however, from a breeders perspective, it provides good information on the genetic potential of a given variety.
Bruce Linquist is the University of California Cooperative Extension rice specialist. He can be reached at email@example.com. Rice Farming editor Vicky Boyd also contributed to this article.