Posts Tagged: Hopland Research and Extension Center
The University of California Hopland Research and Extension Center (HREC) will offer a sheep shearing and basic care Q&A via Zoom from 3 to 4 p.m. May 7. The session will include advice from experienced shearers, flock managers and fiber experts.
Presentations and discussion will focus on shearing that limits stress to both the sheep and shearer. We also encourage your questions regarding sheep handling, husbandry, flock health, running a mobile shearing service, ethical shearing, grazing for fuel reduction and climate beneficial ranching practices. This webinar will take the place of the planned Sheep Shearing and Basic Care 101 immersive workshop planned at HREC in Spring 2020.
Participants in the webinar may also be interested in learning more about the class planned for 2021. Due to these unprecedented times, you do not have to have been registered for the Sheep Shearing 101 class to attend this Q&A session.
The session is free, but registration is required. Click here to register for the webinar and to share your questions.
King is a shepherd focused on intensive rotational grazing for soil building, ecosystem restoration, fuel reduction and nutrient/water cycling. She raises Icelandic and Targhee sheep and sells meat, wool, and pelts through direct marketing. Services she offers include sheep shearing and contract grazing.
Smith is the shepherd of the flock of over 200 sheep at the UC Hopland Research and Extension Center. She also supports research and extension at the site.
Owner/operator of Hollenback Shearing, Hollenback has been professionally trained and employed as a shearer in the United States, New Zealand, Australia, and Austria. His primary focus in shearing is limiting stress to both the sheep and shearer.
Burgess is the executive director of Fibershed, chair of the board for Carbon Cycle Institute, and the author of “Harvesting Color.” A vocationally trained weaver and natural dyer, she creates hands-on curricula that focus on restoration ecology and fiber systems. Burgess has built an extensive network of farmers and artisans in the Northern California Fibershed to pilot an innovative fiber systems model at the community scale.
UPDATED: Viticultural area is Kelsey Bench, not Kelseyville Bench.
UC Cooperative Extension study shows smoke damage to grapes not uniform across vineyards
By the time the Mendocino Complex Fires were officially contained on Oct. 4, 2018, five weeks after igniting, they had burned approximately 450,000 acres in Colusa, Lake, Glenn and Mendocino counties, making it the largest wildfire in California history, according to CalFire.
The fire not only destroyed 280 homes and other buildings, its smoke destroyed the market for wine grapes grown in vineyards near burned areas.
Fearing grapes near the fire would impart smoke flavors to the wine, some wineries rejected all fruit from nearby regions of Lake County and Potter Valley, leaving grape growers to hastily find new destinations for their 2018 crop.
“It can be difficult to determine if fruit has been compromised in quality when exposed to wildfire smoke, and whether or not smoke flavors will result in wine when fermented,” said Glenn McGourty, UC Cooperative Extension advisor in Mendocino County.
A new UC Cooperative Extension study shows wind direction and speed, temperature and a vineyard's proximity to an active fire are factors that can help growers and winemakers predict smoke damage to fruit.
“Fruit in my own vineyard, 60 feet across the street from where the fire started, had no smoke damage because the wind was blowing away from it,” McGourty said.
Due to the Mendocino Complex Fires, an estimated $41 million worth of winegrapes, which would have been sold at full price, were impacted – some were sold at a discount, some were sold to other customers, some were custom crushed, while some were left hanging in the vineyard, according to the Lake County Winegrape Commission and Mendocino County Farm Bureau.
The wine industry needed a scientific method of determining whether grapes could be made into a wine untainted by smoke. With funding from the Lake County Winegrape Commission, McGourty formed a workgroup of local growers and winemakers with Anita Olberholster, UC Cooperative Extension enology specialist in the Department of Viticulture & Enology at UC Davis, to research when fruit quality has been compromised.
“The need for industry standards regarding the impact of wildland smoke on winegrapes and the resulting wines has become even more pressing over the past few years,” said Debra Sommerfield, president of the Lake County Winegrape Commission.
Science showed the intensity, duration and timing of the exposure to wildfire smoke affects the grape's uptake. Generally, the closer to harvest, the greater risk to the fruit.
“Both the fruit and wine samples in our study showed a wide range of volatile phenol and glycocide concentrations, indicating that smoke damage to fruit was not uniform across the vineyards sampled,” McGourty said.
Volatile phenols and glycosides create off-flavors
Fresh smoke contains volatile phenols and glycosides that can affect fruit, but these chemicals tend to dissipate in the atmosphere in 1 to 2 hours. Vineyards close to actively burning fires and in the path of fresh smoke are most likely to be affected by smoke taint. Smoke that travels long distances is less likely to affect grapes and the wine made from the fruit.
The combination of volatile phenols and glycosides create “smoke taint” – both aromatic and tactile in the mouth. Wine drinkers may smell smoke or other off flavors and experience a drying of their mouth when high concentrations of the chemicals are present in wine.
“At lower concentrations, smoke taint reminds you of brett-affected wines,” Oberholster explained, referring to the yeast brettanomyces. “There is a shortness of fruit, a kind of dryness in the mouth that you know isn't normal. There may be barely perceptible aromas that aren't normal as well.”
Following wildfire smoke exposure, the researchers sampled fruit from 14 cabernet sauvignon vineyards around the viticultural areas of Lake County, including Upper Lake, High Valley, Big Valley, Kelsey Bench, Red Hills, Lower Lake and Guenoc Valley. As a control, fruit was also sampled from a Napa Valley vineyard that was not exposed to wildfire smoke.
“The volatile phenols guaiacol and 4-methyl guaiacol are detected in the fruit by gas chromatography, so it is possible to sample fruit before harvest to make picking decisions,” McGourty said. “Based on our study, berry sampling and guaiacol/ 4-methyl guaiacol analysis are useful for a quick evaluation of whether or not fruit from a particular vineyard may have the presence of volatile phenols that can potentially result in smoke-affected wine.”
Testing the fruit for volatile phenols and glycosides is both expensive and not completely predictive as standards are not well defined for damage based on smoke chemical concentration, he cautioned.
These two compounds aren't the only ones that cause smoke flavors. More than 70 other compounds in forest fire smoke can also produce undesirable flavors and odors described as “like licking an ash tray, burnt garbage, a burnt potato, a campfire that has been drenched with water.”
The taste test
To assess the levels of the compounds that produce the off-flavors, Oberholster convened a panel of 14 wine industry professionals to taste the sample wines. The wine tasters detected stronger off-flavors in the wines made from riper fruit, which also contained higher concentration of smoke compounds. Less than 6 micrograms per liter of the smoke compounds were difficult for the tasters to detect, leading the researchers to conclude they will have a minimal effect on wine quality.
Smoke from a distant fire
The scientists also looked at the influence of distance from the fire and elevation on smoke taint. They found some vineyards close to the edge of fires and immediately downwind were heavily affected, with the grapes containing high concentrations of the smoke flavor-causing compounds. But they determined elevation was not a factor in smoke flavors in wines.
Wind direction and speed, temperature and vineyard proximity to active fires are highly likely affect whether there will be smoke damage to the fruit, their research showed.
“Smoke generated in the first one or two hours from a wildfire is most damaging to nearby vineyards,” McGourty said. “Even though a vineyard may be enveloped in smoke, if the source of the smoke is from a distant fire, it will probably won't seriously damage the fruit quality because most of the volatile gases are gone.”
Lake County Winegrape Commission's Sommerfield said, “Today, the results of this study are already proving to be useful in deepening our understanding of smoke and the risks it poses to grapes and wine, in enabling grape growers and winery buyers to engage in fruitful discussions and make informed decisions, and, in turn, in helping to propel the development of industry standards and protocols.”
To read more about the study by McGourty, Michael I. Jones, Oberholster and Ryan Keiffer, see the January 2020 edition of Wine Business Monthly at https://www.winebusiness.com/wbm.
“This is a great little study, the first one that I know of that takes a systems approach to evaluating the effects of wildfire smoke,” said McGourty.
Glenn McGourty, UCCE viticulture advisor for Mendocino County, describes for Hannah Bird the UC project to analyze the effect of wildfire smoke on winegrapes.
Reporter Justine Frederiksen of the Ukiah Daily Journal also reported on the sold-out sheep shearing and wool classing training at the 5,300-acre Mendocino County research center.
“And 60 percent of these people had never even touched a sheep before,” said John Harper, UCCE advisor and shearing school leader. Nearly all the students were women and included an artist from San Francisco, a retired fire chief, a UC Davis graduate student, and a woman who was learning to shear ahead of travels to New Zealand “because I think it will be a good skill to have for work, in case I want to stay for a couple of months.”
“One of the things new students have the most trouble with is what we call ‘tipping' the sheep, or flipping them over,” Harper said. He explained that, to get the sheep into the ideal starting position, you need to push its back legs down with one hand and tuck its head in with the other, twisting the animal into a sitting position with all four legs dangling.
UC Hopland REC sheep shearing students are part of a new wave of sheep shearers and wool enthusiasts industry officials hope will reverse decades of disinterest and decline. The shearing classes were booked well ahead of time, said Hannah Bird, a community educator at the research station. Many students are seeking a break from city life or jobs tying them to a desk.
Wrote reporter Glenda Anderson, shearing sheep is sweaty, back-straining work that earns just $2 to $5 per sheep. But an expert sheep shearer taking part in the program said sheep shearing for a living has its benefits.
“It's a lifestyle thing. I could work six months a year and travel around the world,” paying for the travel by working here and there, he said.
The prescribed burn was carefully orchestrated by CalFire. Wide swaths of vegetation had been cleared around the 7-acre and 9-acre study areas and the weather carefully monitored before a truck-mounted “terra torch” sent streams of flammable gel into the brush, igniting a raging fire.
The fires at Hopland set up a study for a UC Berkeley doctoral student researching post-fire nitrogen cycling, provided a training ground for new CalFire recruits who will be battling blazes in the summer, and launched a new partnership between HREC and CalFire.
Chaparral shrublands, which cover about 7 percent of California natural lands, are vital California ecosystems. Chaparral contains 25 percent of the state's endemic plant and animal diversity. Nature and Native Americans burned chaparral at regular intervals for millennia, providing fresh new growth for foraging animals.
“After a chaparral fire, you typically get a flush of ephemeral wildflowers, some of which are very rare, which you haven't seen for 30 years or since the last fire,” said Lindsey Hendricks-Franco, a doctoral student at UC Berkeley who is conducting research at Hopland. “The amazing thing about these plants is their seeds can survive in the seedbank for decades. Then heat or smoke or an open canopy can stimulate them to germinate. It can be beautiful.”
The most abundant plant in Hopland chaparral, chamise, is barely fazed by fire. The plant's underground burl will soon sprout after a fire, and chamise seeds readily germinate in ash-enriched soil.
To understand the role of nitrogen cycling in the post-fire chaparral ecosystem, Hendricks-Franco and her research staff clambered over dense brush before the fire to collect soil samples and place ingenious heat sensors that document the burn temperature. After the fire, she returned to each site to collect post-treatment soil samples and heat sensors.
“It's a challenge to put sensors in a fire this hot. Most heat sensors are destroyed by the intense heat,” Hendricks-Franco said. “I painted four- by four-inch tiles with a variety of heat-sensitive paints. The paints change color at different temperatures. When I collect the tiles, they will give me an idea about the temperatures reached in the fire.”
The controlled burn at Hopland was the first step in rebuilding a partnership with CalFire, said Kim Rodrigues, who has served as the facility's director since 2014. The areas burned in April were previously burned by CalFire for fire research in the 1990s.
“We've been here since 1951 offering applied and relevant research,” Rodrigues said. “It's primarily research on ecosystem management in oak woodlands, grassland and chaparral. Fire on the landscape is a management tool.”
The 5,800-acre research facility is one of nine such centers managed by UC Agriculture and Natural Resources in a variety of California ecosystems, from high desert near the Oregon border, low desert in the Imperial Valley, Sierra Nevada forests and San Joaquin Valley farmland. Hopland is also home to 500 sheep.
Hopland CalFire battalion chief Michael Maynard was the incident commander at the April controlled burns, which he said also fulfilled CalFire objectives.
“It's good to be back here to join up with the University of California,” Maynard said. “The fire falls into our realm of training and expertise and we're helping their realm of expertise, which is research. There are 10 plots on this specific research project, so we'll be back soon.”
Maynard brought in newly hired firefighters for training on setting and controlling a prescribed burn.
“It's important that we brush up on our skills. We have seasonal employees that have hired on early and are participating. So the all-around training value is incredible and pays off later in the summer,” Maynard said.
CalFire will be back at Hopland in the fall to implement another chaparral burn so Hendricks-Franco can compare the fate of nitrogen in areas that burn before the hot, dry summer season to areas that burn in the fall and are followed by rain.
View scenes from the controlled burn in the video below:
Mendocino County supervisors decided to sever ties with the USDA's division of Wildlife Services, reported Peter Fimrite in the San Francisco Chronicle. The decision was made after environmental groups said the agency was indiscriminately killing predators, such as mountain lions and coyotes, because they are a threat to livestock.
The article featured a gallery of 10 artful photos taken at the UC Hopland Research and Extension Center, which maintains a research sheep flock of 500 breeding ewes. Record-keeping of sheep losses to predators began at Hopland in 1973. Coyotes are the most serious predator problem.
Hopland staff use a variety of non-lethal and preventative methods to protect sheep from predators, such as fencing, mob grazing and frequent pasture rotation and guard dogs, according to Kim Rodrigues, the director of the research and extension facility. Currently there are five guard dogs at the center. The guard dogs bond with sheep and protect them primarily by barking and other aggressive behaviors when strangers or predators are near the sheep flock.