Organic farmer Phil Foster has developed a creative way to nurture the soil on his 200-acre farm near Hollister. He plants cover crops in a single line at the top of the planting bed, saving water and seed while keeping the furrows clear for irrigation.
"We were finding we couldn't use cover crops because of water," Foster said. The narrow strip makes the best use of the limited water supply, while garnering the benefits of cover crops - which buffer soil temperatures, inhibit weeds, increase soil microbial activity, improve water infiltration and add nutrients. Growing cover crops prepares the soil for the production of high-quality vegetables.
Foster is one of eight organic vegetable growers who are working with researchers at Chico State, Fresno State and UC Agriculture and Natural Resources on a project funded with a USDA grant designed to make significant improvements in soil care in organic production systems. He guided project participants around his farm, equipment yard and compost operation in early November to share the techniques he and his staff have developed over three decades to promote soil health.
Tour participants marveled at the soil characteristics, admiring tiny pores and roots in clods of dirt, evidence of the soil's capacity to move water and nutrients. They studied the plant and soil conditions after farm manager Efrain Contreras pulled a carefully crafted implement for rolling down the cover crop across the field with a tractor.
Foster credited Contreras, a 30-year employee, for his role in building the soil on the farm. Labor, Foster said, is his biggest cost. He has 50 full time staff, many with 5 to 20 years of experience.
"They are the key to to the success of the ranch," Foster said.
Minimizing and, eventually eliminating, soil disturbance can be combined with organic groundcover, year-round root growth and robust biological activity in the soil to further promote soil health. Following the tour, the farmers talked about ways to attain the goal on their farms of no-till organic vegetable production.
Foster said he will experiment with reducing soil disturbance to determine whether doing so will maintain or increase yields. Another farmer in the project, Scott Park of Meridian, Calif., 50 miles north of Sacramento, said he will dedicate eight acres of his organic farm to comparing the results when the cover crop is chopped and left on the soil surface to chopped and incorporated with tillage.
Paul Muller and Andrew Braitt of Fully Belly Farm in the Capay Valley suggested the researchers could help the farmers by identifying optimal, effective cover crop rolling techniques. Retired organic farmer Tom Willey of Madera suggested grant funds be used to purchase appropriate scale cover crop seeders for on-farm experimentation.
"We're making great progress," said project coordinator Jeff Mitchell, UC Cooperative Extension vegetable crops specialist. "By getting together regularly, we're seeing opportunities for moving further toward reduced-disturbance on the farms, identifying the equipment needs and establishing effective channels of communication."
Over the project's three-year term, the farmers and researchers will continue to experiment with soil-building techniques and share results.
Recently I was asked to help identify prostrate knotweed (Polygonum aviculare) that was collected from an alfalfa field. Admittedly, the tough and wire-like specimen that was submitted to me at the end of autumn didn't much resemble the succulent...
Great to have Michael Jones our new UCCE Forestry Advisor in post! Read more about Michael here:
For millennia, fires periodically burned through California forests, thinning trees, reducing shrubbery and clearing out downed branches and debris. Without periodic fire, the forests became more dense, with spaces between large trees filling in with a thick carpet of duff, seedlings and shrubs.
As a result, today's forests are prone to more intense and damaging fires, like the Rim Fire, King Fire, and — most recently — the Camp Fire in Butte County. These fires are burning with unprecedented severity and speed, threatening large swaths of forest, towns, and even urban areas.
Using fire as part of forest management is not a new concept. Native Americans were known to burn brush to open up hunting grounds and clear shrubbery for gathering. Decades ago, iconic Berkeley forestry professor Harold Biswell said, “Fire in the Sierra Nevada is as important as rain.”
Competing forces, however, pushed foresters and fire officials toward fire prevention and suppression, particularly the cataclysmic fires of the early 20th century that leveled entire towns and left dozens of residents and firefighters dead. The fear of out-of-control blazes and the perceived damage to timber resources launched a war on fire that has lasted a hundred years. Some forest managers are urgently trying to negotiate a truce.
Making peace with fire and turning it into a useful tool, rather than a raging threat, was the objective of an October meeting in Shaver Lake of UC Cooperative Extension forestry and natural resources scientists, Southern California Edison forest managers, CALFIRE officials and U.S. Forest Service representatives.
The event also raised awareness of “pyrosilviculture,” a new forest management term coined by UC fire scientist Rob York to emphasize the importance of fire in silviculture, the management of forests for wood.
Forests have myriad benefits – recreational, environmental and economic. Nature lovers value the whisper of pine trees in the wind and green shade over hiking trails and ski slopes. Owls, bears, deer and other wildlife make their homes among firs, pines, oaks and cedars. Forests stabilize mountain slopes, which store water as snow for agriculture and drinking. People build their homes, businesses and schools out of the planks and boards cut from the straight, soft wood of conifer trees.
The value of California forest products was about $429 million in 2017, according to the USDA. Because fires can damage and destroy trees, the timber industry has historically been reluctant to use fire as a tool. That's changing.
“Fire is such an important ecological process, you can't manage for timber without fire,” York said.
York is the manager of the Blodgett Forest Research Station, UC Berkeley's 4,000-acre mixed conifer and oak forest near Georgetown where researchers study forest management practices for increasing timber yield while taking advantage of fire to enhance forest health and make forest stands more resilient to wildfire.
Controlled burning can be used to treat fuels and reverse these trends, but it has been inhibited by a number of barriers, including landowners' concerns about liability, risk aversion among fire management agencies, narrow burn windows, air quality limitations and other regulatory challenges. Now, public demand for prescribed fires is growing.
“I believe what moved the needle was, for several years in a row, there were high-severity fires in the news,” York said. “Wildfires were in the pubic zeitgeist. People began asking, ‘Why aren't we doing more prescribed fire?'”
Climate change is also intensifying the interest among the public and silviculture professionals. Because California is getting warmer and fire seasons are growing longer, high-severity fires are expected to increase.
“There would logically be a tipping point. Even though we reduce the growth of trees when we use fire, if it can prevent the loss of the forest entirely, it would be meeting the timber objective,” York said.
The vast tree die-off during the 2011-2016 drought was another jarring sign that the Sierra Nevada ecosystem is out of balance.
The U.S. Forest Service, which manages 20 million acres of forest in California, is using prescribed fire to reduce fire risk on federal forestlands, but scientists say it's not nearly enough to reduce the threat of catastrophic wildfire. CAL FIRE is ramping up its controlled burn efforts, but it will take time to address far-reaching areas of overgrown forestlands. The agency sometimes uses mechanical measures such as mastication and chaining before burning to pre-treat fuels and prepare units for burning.
“We need to work around communities first, and then move out to the wider landscape,” said CAL FIRE division chief Jim McDougald. “If a prescribed fire moves into a subdivision and burns houses, we take 100 steps back.”
“Burning is a key element of forestland management and it can be safe if done properly,” Kocher said. “We provide classroom instruction and invite participants to join a live prescribed fire at Blodgett Forest as part of their training so they become familiar with the process.”
At the training sessions, UC Cooperative Extension advisor Lenya Quinn-Davidson said that in some cases, private landowners can conduct burns themselves. In her hometown in Trinity County, many ranchers and landowners conduct small broadcast burns to reduce fuels and improve forage. These burns are typically quite small and usually conducted in the winter.
“This can be a good option for landowners who wish to burn small areas, but we need other options for bigger, more complex burns” Quinn-Davidson said.
In other parts of the country, landowners have formed Prescribed Burn Associations (PBAs) that allow landowners to work with neighbors and other community members on controlled burns, sharing equipment and labor while developing skills. The PBA model provides a low-cost, grassroots option for prescribed burning, and empowers landowners to work together, and with other key experts and partners, to bring fire back to the landscape, says Quinn-Davidson.
“People are desperate to do something about fire, and the PBA model gives them an option to actively engage with each other and with fire as a tool—it's very empowering,” said Quinn-Davidson.
From the Retail Nursery an Garden Center IPM News Fall 2018 newsletter Managing Weeds in Landscapes Nurseries and garden centers often sell a wide range of plants for use in gardens and landscapes. Your customers may manage a complex array of different...