Posts Tagged: organic
California’s scenic Marin County is home to two thriving industries that were once in conflict – oyster farming and dairy farming.
In order to grow healthy and marketable oysters, the farmers depended on clean water in Tomales Bay. But regulations meant to protect the bay from cattle runoff were so strict that dairy farmers feared they could no longer stay in business.
Now, with help from David Lewis, director of UC Cooperative Extension in Marin County, these two communities have found creative solutions that allow both kinds of farmers to share this beautiful and fertile region. Find out how in a four-minute report by Kristen Simoes on UCTV Prime Cuts, “Cooperation Trumps Conflict in Tomales Bay.”
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.
For conventional growers, chemical herbicides have taken the drudgery out of weed control. For organic farmers, weeds continue to be a perennial headache.
Many large-scale organic growers have turned to mechanical cultivators to dislodge weeds. However, standard cultivation systems leave an untouched band of soil around the seedlings that must be cleared by hand. This hand labor often represents a large part of total production expenses.
Richard Smith, a UC Cooperative Extension advisor in Monterey County who specializes in vegetable production and weed control, heard about “finger weeders” while at a conference in Germany.
“There is a brand available in the U.S., but the European design is much better,” Smith said.
He purchased a finger weeder from the German Kress Company and conducted trials on commercial farms in Monterey County to assess their effectiveness in organic vegetable production. With this system, hard plastic discs with long fingers are pulled by a tractor horizontally down the field, dislodging recently germinated weeds while leaving transplanted vegetables unharmed.
The timing of cultivation is critical. For transplanted vegetables, the cultivation must be done after the plants are firmly rooted and weed seedlings have just one small, tender root. Soil moisture also influences the effectiveness of the finger weeder.
In a trial Smith conducted on organic leeks, the finger weeder removed 80 percent of weeds, while the standard cultivator removed 29 percent. Hand weeding time was reduced by 45 percent, from 19 hours per acre to 10 hours per acre. The yield of the leeks was not affected by the finger weeder cultivation.
On an organic radicchio farm, the finger weeder removed 81 percent of weeds, while the standard cultivator reduced 48 percent. Hand weeding time was reduced 44 percent, and the yield was unaffected.
In six out of eight trials, the finger weeder significantly reduced hand weeding time compared to standard cultivation.
“We want to raise awareness among our growers that this is a viable option for weed control on organic farms,” Smith said.
Smith is also studying other high-technology organic weed control systems, such as computer-guided cultivation equipment.
“There is tremendous potential in this technology, but it is very expensive,” Smith said.
For more information on organic weeding options, see the video below: