Cooperative Extension San Joaquin County
University of California
Cooperative Extension San Joaquin County

Posts Tagged: Dan Putnam

UC scientists helping farmers reduce water needs

Rain in December raised hopes for an end to the California drought, but storms have stayed away since the New Year began. January 2015 is shaping up to be the driest January since officials began keeping records 137 years ago, according to the National Weather Service.

California's continuing water crisis is leading to decreased and more variable water supplies for San Joaquin Valley farmers, and the region's forage production sector is being hit particularly hard.

“Corn silage and alfalfa have traditionally used lots of water and current and future water restrictions are forcing many farmers to rethink their forage production strategies,” said Jeff Dahlberg, UC Cooperative Extension specialist. “I know of one dairy that had to cut-off their summer irrigations of alfalfa to get their corn silage done.”

To help the agriculture industry make do with less water, a team of UC researchers began a long-term research project last year by growing alfalfa, sorghum and corn under a state-of-the-art center pivot irrigation system. The system, donated by industry partners, is installed at the UC West Side Research and Extension Center near Five Points. Reinke Inc. donated the center pivot, Senninger Irrigation donated nozzles, and Rain for Rent created the infrastructure that gets water and power to the 16-acre research plot.

“We see tremendous possibilities for overhead irrigation in cotton, alfalfa, corn, onions and wheat production,” said Jeff Mitchell, UC Cooperative Extension specialist and the project lead. “There is also great potential for overhead irrigation in California's $5 billion dairy industry for more efficiently producing feed crops like alfalfa, corn and sorghum.”

All aspects of production – including irrigation system performance, crop growth and development, weed control, water application, and economic viability – are being monitored by researchers from UC Cooperative Extension, Fresno State University and UC Davis, plus farmer cooperators and industry partners.

The primary focus of the study is comparing regular irrigation levels with regulated deficit irrigation, a system in which water is withheld at certain times in crop development in order to minimize crop losses even when water is short.

The overhead irrigation system allows researchers to make precise adjustments in water delivery.
“By controlling the speed of the pivot and by using special water application nozzles that apply precise and different amounts of water, we will get either full irrigation, three-quarters of the full amount or about half of the full irrigation quantity over the course of the season,” Mitchell said.

The researchers will apply small, precise amounts of water during the vegetative growth stage for sorghum and both immediately before and after monthly harvests and during the mid- to late-summer period for alfalfa when San Joaquin Valley productivity typically is reduced under flood irrigation.

“We expect to produce marketable and economic yields for sorghum using 25 percent less water as has been achieved under pivots in Texas and similar increases in crop water productivity for alfalfa,” Mitchell said. “This work will inform and improve future water management strategies in California.”

Overhead irrigation systems, such as center pivot systems, are the most prevalent form of irrigation nationwide; however, they have not been widely adopted in California to date. Recent technological advances in overhead irrigation – which allows integration of irrigation with global positioning systems (GPS) and management of vast acreage from a computer or smart phone – have boosted farmers' interest in converting from gravity-fed surface irrigation systems, which are still used on 5 million acres of California farmland.

The research is funded in part with a grant from the UC California Institute for Water Resources. In addition to Dahlberg and Mitchell, UC Cooperative Extension alfalfa specialist Dan Putnam and UCCE advisor in Fresno County Dan Munk are collaborators on the project.

An initiative to improve California water quality, quantity and security is part of the UC Division of Agriculture and Natural Resources Strategic Vision 2025.

The center pivot system at the UC West Side Research and Extension Center before crops were planted.
The center pivot system at the UC West Side Research and Extension Center before crops were planted.

Posted on Monday, January 26, 2015 at 9:20 AM

New GMO alfalfa holds exciting possibilities, UC expert says

Growers can produce more nutritious alfalfa using new low-lignin variety, says UCCE's Dan Putnam.
Good news for dairy cows. Science has found a way to produce alfalfa with less lignin, a component of the plant that has no nutritional value. The new alfalfa variety – genetically modified in a way that puts brakes on the lignin-producing gene – was deregulated by USDA in November.

“In general, a reduced lignin trait in alfalfa is very welcome,” said Dan Putnam, UC Cooperative Extension specialist in the Department of Plant Sciences at UC Davis. “The low-lignin trait has some interesting potential implications for dairy cows and other ruminants, as well as for yield, agronomic efficiency, and even energy and water use efficiency.”

The new variety, called KK179, was developed by Forage Genetics International, Monsanto and the Nobel Foundation. Some of the field testing took place at UC Davis and the UC Intermountain Research and Extension Center in Tulelake, Calif.

KK179 differs from most other GMO agricultural crops in that the modification improves the plant quality. Other common modifications, such as glyphosate resistance and addition of a Bt gene, were designed to help with pest control.

Another difference is the source of the modified gene, Putnam said. In glyphosate-resistant (Roundup Ready) alfalfa, for example, the plant was modified by inserting a bacteria gene. Gene segments reducing lignin were derived from alfalfa itself.

Lignin is a fibrous part of cell walls in plants. It strengthens stems, helping the plant grow upright. However, its concentration in alfalfa is high compared to other forages, a drawback for what is considered the premiere forage of dairy cows.

“Farmers often try to cut early to reduce lignin,” Putnam said. “Unfortunately, yields are decreased by early cutting, often by many tons per acre. If growers were able to harvest later and still obtain good quality, yields would improve.”

That leads to the potential energy- and water-conserving aspects of the KK179 alfalfa.

“If growers reduce harvests by one each year and increase yields with no quality penalty, energy use would decline,” Putnam said. “Also, the amount of milk produced per unit of water used to grow the feed may be increased.”

KK179 won't be for everybody, Putnam cautions. Some export markets reject GMO technology, so growers should check whether their markets will accept alfalfa with the low-lignin trait. Another concern is the possibility of gene flow for farmers who grow alfalfa seed for organic production or export.

“Further research and experience by farmers and researchers are needed to fully understand the importance and implications of reduced-lignin alfalfa on farms,” Putnam said, “but this trait holds some very exciting possibilities.”

An initiative to enhance competitive and sustainable food systems is part of the UC Division of Agriculture and Natural Resources Strategic Vision 2025

Posted on Tuesday, December 16, 2014 at 8:13 AM
Tags: alfalfa (7), Dan Putnam (4), GMO (1)

UC scientists wrestle with weed control in organic alfalfa

During the 2000s, organic milk production was one of the fastest growing segments of organic agriculture in the United States, according to a USDA Economic Research Service publication Characteristics, Costs, and Issues for Organic Dairy Farming. In 2008, about 3 percent of the nation's cows were managed organically.

Among the conditions necessary for a cow to produce organic milk, she must eat only organic feed or browse on organic pasture for at least the previous 36 months. However, dairy producers have found that producing or sourcing organic feed – which must be grown with no synthetic fertilizers, insecticides or herbicides – is challenging. Recently organic alfalfa made up nearly 1.4 percent of U.S. alfalfa hay production, up from .5 percent in the early 2000s.

Dan Putnam, UC Cooperative Extension specialist in the Department of Plant Sciences at UC Davis, an alfalfa expert, said one key obstacle for organic alfalfa producers is weed management. Putnam put together a team of alfalfa hay experts to conduct an alfalfa weed management trial at the UC Kearney Agricultural Research and Extension Center, where 10 acres are set aside to research organic production.

In 2011, Putnam; Carol Frate, UCCE advisor in Tulare County; and Shannon Mueller, UCCE advisor in Fresno County, experimented with timing seeding and early clipping to manage organic alfalfa in a weedy field.

“Alfalfa can be planted from early September all the way through the fall and winter to early spring, depending on weather patterns,” Putnam said. “Many farmers plant in late November and wait for rain to bring the crop up. Other options are irrigating the crop up in early fall or waiting till early or late spring to plant the crop. All of these strategies have implications for weed management.”

The late November planting is quite common since, compared to a September planting, it saves farmers the trouble of putting out sprinklers. However, late fall plantings failed in this experiment.

“We had a lot of weed intrusion at that point as well as cold conditions for alfalfa growth, so the stands were poor,” Putnam said.

The earlier planting also had weed intrusion, but the researchers clipped the field when the alfalfa was 10 to 12 inches high in early spring. The clipping cut back weeds that were overtopping the alfalfa, giving an advantage to the vigorous young alfalfa seedlings.

An early spring planting after tillage to destroy weeds also resulted in a good stand, but some production was lost in the first year compared with early fall plantings.

“Many growers are starting to realize that early fall (September/October) is a better time to start their alfalfa crops,” Putnam said. “With organic growers, it is even more important to pay attention to time of seeding because they have so few weed control options.”

While this research is conducted on organic alfalfa, Putnam said the results are also applicable to conventional alfalfa production, which represents more than 98 percent of California's total alfalfa crop.

“Timing has a profound effect on the first-year yield and health of the crop and its ability to compete with weeds,” he said.

Putnam, Mueller and Frate will share more information about the organic alfalfa trial during a field day at Kearney, 9240 S. Riverband Ave., Parlier, from 8 a.m. to 12 noon Sept. 5. The field day will feature the organic production trials, alfalfa variety trials, sorghum silage and nitrogen trials, and optimizing small grain yields. Other topics will be alfalfa pest management, irrigation and stand establishment.

Ten acres at Kearney are set aside for organic research.
Ten acres at Kearney are set aside for organic research.

Posted on Wednesday, July 11, 2012 at 8:41 AM
Tags: alfalfa (7), Dan Putnam (4), organic (9)

Green energy may generate more greenbacks for farmers

California’s role as an emerging world leader in the development of green energy technologies offers the state’s farmers the opportunity to diversify their cropping systems and increase their income.

Sacramento lawmakers have given the California Energy Commission an annual budget of $100 million to support the development of alternative and renewable low-carbon fuels. In addition, the State Alternative Fuels Plan set goals of reducing petroleum dependence by 15 percent and increasing alternative fuels use by 20 percent by 2020. These efforts are meant to help meet the growing fuel demands of the world population while reducing greenhouse gas emissions in California to 1990 levels.

“With the new mandates, there are new opportunities for using agricultural waste and dedicated energy crops for biofuels, but we’re not yet sure exactly what form it will take,” said UC Cooperative Extension alfalfa specialist Dan Putnam. “I would always encourage growers to experiment with the crop, but I wouldn’t jump in whole hog unless I had a buyer lined up.”

Switchgrass is a potential biofuel crop.

U.S. ethanol production in January 2010 was 818,000 barrels per day, according to the U.S. Energy Information Administration. The United States uses about 20 million barrels of oil per day. If the EPA allows up to 15 percent ethanol blends for all vehicles, then the 10 million barrels per day of oil used by cars and trucks could allow ethanol and biofuels to make up 1.5 million barrels per day.

Cellulosic biomass is the only known resource for the sustainable production of liquid transportation fuels on a large scale and at low costs, according to UC Riverside environmental engineer C. W. Wyman.  Cellulosic biomass includes agricultural residues such as corn stems and leaves, forestry residues such as sawdust and paper, landscape waste, herbaceous plants such as switchgrass and sorghum, and woody plants such as poplar trees.

Since a dry ton of cellulosic biomass could provide about three times as much energy as a barrel of petroleum, the cellulosic biomass would have three times the value as a barrel of petroleum. That means cellulosic biomass would be worth about $200 per dry ton when crude oil sells at $65 per barrel.

“To utilize this abundant resource, we must develop low-cost technologies for transforming biomass into fuels that can compete with petroleum,” Wyman wrote in a California Agriculture article “Cellulosic biomass could meet California’s transportation fuel needs.”

Current and potential biomass crops include the grasses switchgrass and miscanthus, other perennial grasses, plus high biomass sorghum, alfalfa and other crops.

Across California, University of California scientists are studying potential biofuel crops. Putnam has four research trials under way, testing varieties from Ceres and Mendel Biotechnology, Inc.  He said switchgrass and miscanthus the top contenders so far in his trials.

“The yields of switchgrass under irrigation have been quite high,” Putnam said. “It is an efficient crop for converting solar energy into biomass under warm weather condition.”

Switchgrass does have relatively high water needs. Putname said scientists are looking into whether the crop can be grown under deficit irrigation to save water and still produce the biomass.

“The key issue with biofuels is not necessarily the total water requirement, but the water use efficiency and amount of biomass produced per unit of water,” Putnam said. “Even if a crop has high water use, if it produces a large amount of biomass, it may still be the best option.”

Steve Kaffka and UC Cooperative Extension advisors are involved in research on winter annual oilseeds such as canola, camelina and meadowfoam as potential biofuel feedstock crops.

“Recent economic modeling we have done suggests that at current market prices, canola is a competitive crop in California, but outlets have not yet developed for the seed,” Kaffka said. “Currently, petroleum prices are too low to support the use of canola for biofuel feedstocks, but that is changing rapidly. “

The director of the UC Kearney Research and Extension Center, Jeff Dahlberg, sees opportunities for California production of sorghum as a biofuel crop.

"Sorghum is one of the few crops that span all the different renewable fuel options," he said. "You can use the grain to convert into ethanol. We have sweet sorghum, a specialty sorghum which is very similar to sugar cane. You can press the juice out and convert it into ethanol. And, we can produce a lot of biomass."

Dahlberg previously served as research director for the National Sorghum Producers and the research director for the United Sorghum Checkoff Program in Lubbock, Tex. He currently is lead investigator on a $984,000 U.S. Department of Energy grant to study the composition of sorghum and its potential for cellulosic conversion to biofuel. In addition to continuing this research at Kearney, Dahlberg is interested in developing a center for on-farm green technologies at the Central California research station.

Posted on Wednesday, January 19, 2011 at 7:05 AM
Tags: biofuel (6), canola (1), Dan Putnam (4), energy (5), green (2), Jeff Dahlberg (7), sorghum (3), Steve Kaffka (2), switchgrass (2)
 
E-mail
 
Webmaster Email: mdhachman@ucdavis.edu