The beauty of rolling hills studded with majestic oaks, other trees and shrubbery isn't the only reason to regenerate vegetation. The trees and shrubs create a much more hospitable habitat for a wide assortment of wildlife. Oak woodland vegetation also protects the quality of California water. The majority of the state’s water flows through oak woodlands in streams and rivers that support fisheries, farms and cities. Plants and trees anchor the soil, preventing erosion and stream sedimentation.
One of the difficulties ranchers face in regenerating trees is supplying water for seedling establishment. Ranches often stretch for thousands of acres. Hauling water to remote sites or installing irrigation can be prohibitively expensive.
Third-generation San Miguel rancher George Work heard about a new tree establishment invention from Holland – a Groasis Waterboxx. Over the years, Work has collaborated with UC Cooperative Extension on oak planting projects and consulted with UCCE experts about squirrel diseases, ranch animal vaccinations and pasture management. He turned to UCCE natural resources advisor Royce Larsen for his thoughts on the Waterboxx.
“Because of Royce here, our Cooperative Extension agent, he provided a little added incentive when I wanted to try this thing,” Work said. “Royce said, ‘I’ll help you.’ Well, that was enough to get the job done.”
Work, Larsen and UC Cooperative Extension natural resources specialist Bill Tietje installed 10 Waterboxxes, which cost about $30 each, in a remote area of the 12,000-acre Work Ranch in southern Monterey County. Other plant regeneration methods – including traditional drip irrigation and tree teepees – were also installed for comparison.
The Waterboxx is a round plastic hat box-shaped reservoir that fits around the seedling trunk. When the seedling is planted, the reservoir is filled with about four gallons of water. A rope on the bottom continuously wicks moisture to the plant roots.
The box is covered with an inward-slanting corrugated top that cools during the night and channels condensed dew and fog into the reservoir, keeping it full of water. The Waterboxx provides a protective barrier around the trunk and shades and cools the soil beneath. At the Work Ranch, the plants are also enclosed in bale-wire fence to keep out wildlife poking around for water or hungry for tender green growth.
“The trees are doing surprisingly well," Larsen said. "In just three months, the seedlings have grown more than two feet."
Larsen said he will continue monitoring the project to see if the self-watering system can establish trees. If successful, UC scientists may study the Waterboxx more thoroughly in a replicated research design in Monterey County, San Luis Obispo County and other parts of the state.
See the components of a Waterboxx in the video clip below.
The Las Conchas fire that recently consumed nearly 137,000 acres in Los Alamos, N.M., serves as a reminder of how quickly fire can move if given fuel. I can’t light a barbecue with matches and lighter fluid, but a small ember drifting on the wind can find so many ways to burn down people’s homes if given the right conditions.
Removal of vegetation near Los Alamos National Laboratory, which is part of the UC system, created a buffer and helped spare the lab from the Las Conchas fire, which came within 50 feet. Creating a buffer is one of many preventive measures that can be taken to protect property from wildfires.
In a wildfire-prone area, even if you have a house with a concrete tile roof and noncombustible siding, an ember landing on landscape mulch, igniting plants around the home or floating into a vent on the house or under decks may set the house ablaze, warns a UC Cooperative Extension fire expert.
“From years of observing the aftermath of fires and testing fire-resistant building materials, we have developed a much better understanding about what happens,” says Steve Quarles, UC Cooperative Extension wood performance and durability advisor.
Quarles lists six priority areas for evaluating the vulnerability of homes in fire hazard zones: the roof, vents, landscape plants, windows, decking and siding. For details on how you can reduce the threat of wildfire to your home, visit Quarles' Homeowner's Wildfire Mitigation Guide.
“We know that the zone within about five feet of the home is very important to home survival during a wildfire,” Quarles says.
Landscape mulch provides many benefits to a garden, but Quarles and his colleague Ed Smith, University of Nevada Cooperative Extension natural resource specialist, found that many types of mulch are capable of catching fire and burning. Within five feet of a house, they recommend placing only rock, pavers, brick chips or well-irrigated, low-combustible plants such as lawn or flowers.
Quarles and Smith have published a new manual comparing the relative susceptibility of eight mulch treatments to igniting and burning. To download a free copy of “The Combustibility of Landscape Mulches,” visit the UC Fire Center website.
The scientists tested eight types of landscape mulches, shown in this test plot.
A very wet spring brought a good deal of water to the floodplains this year—good news for juvenile salmon that thrive in this habitat. Floodplains — such as the Yolo and Sutter Bypass areas and the Cosumnes River floodplains — provide a link for juvenile salmon between the gravel bedded rivers where they hatched and the ocean where they will spend the next one to five years.
Although salmon may only use the floodplain for a month or two, this could mean the difference between success and failure in their long journey to the ocean and back again. When juvenile salmon spend time on the floodplain, they grow faster than those that use only the river channel during their migration to the ocean (Sommer et al. 2001, Jeffres et al. 2006). Because of the increased growth, the juveniles are larger when they head out to sea; they can survive better by swimming faster and being more able to avoid predators.
What makes a floodplain a good place for rearing salmon? First of all, it needs to be connected to the river. This sounds obvious, but most of the floodplain habitat in California is isolated behind levees and only gets flooded during extreme high water events when the levees are overtopped or breached. The reason that the levees are there is to protect housing and agricultural land (orchards, vineyards, etc.), which doesn’t allow for regular inundation of floodwaters.
Why are these multi-purpose floodplains better than the river channel for rearing salmon? As cold floodwater enters a floodplain from the river, it spreads out, slows down and deposits sediment. Throughout this process, the water also warms slightly. This is essentially the priming of the productivity pump that will ultimately feed the juvenile salmon for the next couple of months. As the water slows, clears and warms, phytoplankton and algae begin to grow. Populations of animals that feed on the fast-growing plant life, such as zooplankton and other aquatic invertebrates boom. These animals comprise the main food of juvenile salmon on the floodplains.
Because salmon are cold blooded, water temperature it is an important component to floodplain suitability. If water is too cold, juvenile salmon are lethargic and growth is slow. If the water is too warm it causes increased metabolic demands and reduced dissolved oxygen, inhibiting growth and increasing mortality. Fortunately for California salmonids, out-migration is in the spring when temperatures are generally moderate. The timing of spring high flows onto floodplains allows for ideal temperatures for juvenile salmonids compared to the relatively cold water in the main river channel. When temperatures are good and food is abundant, juvenile salmon can grow at impressively fast rates, especially when compared to fish using the main river channel.
The combination of complex physical processes and ecological function is what separates the floodplain from the river corridor in the eyes of juvenile salmon. Leveed river channels provide little complexity and less than ideal growing conditions during the annual spring out-migration. When juvenile salmon have access to complex floodplain habitats where temperatures are good and food resources are abundant, they will grow to larger sizes and thus be able to survive better than fish that remained in the main river channel.
So, next time you catch a big healthy salmon, thank your local floodplain.
Jeffres, C., J. Opperman and P. Moyle (2008), “Ephemeral floodplain habitats provide best growth conditions for juvenile Chinook salmon in a California river,” Environmental Biology of Fishes 83 (4): 449-458.
Sommer, T., B. Harrell, M. Nobriga, R. Brown, P. Moyle, W. Kimmerer and L. Schemel (2001), “California’s Yolo Bypass: Evidence that flood control can be compatible with fisheries, wetlands, wildlife and agriculture,” Fisheries 26 (8): 6-16.
Pesticides that have not been sold at the retail level for years are still regularly found in residential runoff water, according to research in Sacramento and Orange counties by UC scientists. So called “legacy pesticides” are probably old products that homeowners still have on their garage shelves and are still using to control pests.
An earlier study by the California Department of Pesticide Regulation and the UC Integrated Pest Management Program found that 60 percent of pesticides sold to consumers are for ant control. For that reason, UC Cooperative Extension specialist in landscape horticulture Loren Oki of UC Davis and UC Cooperative Extension water resources/water quality advisor Darren Haver focused on ant control pesticides in their residential runoff research project. The scientists collected 830 water samples from the storm drains in four Sacramento County neighborhoods and four Orange County neighborhoods between 2006 and 2010.
“In Sacramento County, we trained a team of about 25 volunteer UC Master Gardeners to collect the samples,” Oki said. Orange County samples were collected by Haver and his staff. All the samples were sent to UC Riverside for analysis.
“Pesticides that have been off the market since 2004 are still found in the water,” Oki said. “We found organophosphates – diazinon and chlorpyrifos – in differing amounts, typically more in Orange County than Sacramento County. We also found a fairly new pesticide, fipronil, in most of our water samples.”
The scientists also noted random spikes in the amount pesticides in runoff water, unconnected with storms or other conditions, which suggested that they were directly associated with particular pesticide applications in the neighborhoods.
There are several ways homeowners can help prevent contamination of the California water supply. For one, dispose of old pesticides properly. Most cities and counties have programs for disposal of household hazardous waste.
When using pesticides, Oki suggests residents carefully read the label and use common sense.
“Don’t put pesticides on impervious surfaces, like concrete walkways and driveways,” he said. “Don’t put pesticides in garden areas where runoff might be generated. That runoff will carry the pesticides with it.”
Residents can also minimize the amount of water runoff from the property. Oki suggests reducing irrigation and targeting the water application properly. In addition, promote soil infiltration by promoting soil health.
“If you don’t generate runoff, you won’t have pesticides running off too,” Oki said.
Residential runoff can convey pesticides into water supplies.
As it turns out, the farmer and the cowman should be friends, as the classic “Oklahoma!” song suggests. According to a just-published UC Berkeley study, wild bee species pollinate California crops to the tune of $937 million to $2.4 billion per year. That amounts to more than one-third of all pollination “services” to the state’s crops.
Many of those crop-pollinating wild bees live in rangelands – chiefly ranches that graze cattle.
“This means that preserving rangelands has significant economic value, not only to the ranchers who graze their cattle there, but also to farmers who need the pollinators,” said Claire Kremen, UC Berkeley associate professor of environmental science, policy and management, and senior author of the study.
The assumption that wild pollinators were not a significant source of crop pollination is more than just conventional wisdom – it’s business: a majority of farmers rent European honeybees to ensure crop pollination.
But beekeepers have suffered high rates of colony losses due to diseases, pesticides and management factors, increasing the uncertainty of both supply and rental prices.
And wild pollinator species have also shown declines in abundance and diversity on farmlands, most likely due to habitat loss from the intensive monoculture, or single crop, production system that typifies much of California’s agricultural lands.
The result? They are most scarce precisely where they are needed the most.
“Currently, wild pollinators are least abundant in intensive monoculture production areas such as sunflowers, almonds and melons, where demand for pollination services is largest,” said Kremen.
Kremen equated depending mainly on one species – the European honeybee – with putting all our retirement savings in one stock.
“The wisdom of diversification holds true for agriculture as well and yet, many Calfornia farmers rely solely on European honeybees for crop pollination,” Kremen said, adding that the unpredictability associated with climate change amplifies the importance of diversification.
“Some insect species will thrive in changed climate conditions, and other won’t. Maintaining a biodiverse stock of pollinators is like the insurance that a diversified stock portfolio brings: some will be up, some will be down, but having a portfolio of many different species ensures viability into the future,” Kremen said.
While it’s common sense that healthy crops result in a healthy food supply, a separate study led by Kremen, also just published, put a number on the human health benefit of ensuring the viability of pollinators. The researchers estimated that up to 40 percent of some essential nutrients provided by fruits and vegetables could be lost if there were no pollinators around to do the job.
Payment for services rendered
Placing a value on ecosystem services is an established part of conservation science, and this new finding comes at a time when there is growing interest within the ranching community in providing ecosystem services. For example, as part of conservation efforts, California ranchers have been asked to maintain flowers for endangered butterflies and to keep small spring wetlands known as vernal pools healthy – using grazing as a tool to manipulate the grassland.
Darrel Sweet, a fifth generation cattle rancher from Livermore and a former president of the California Cattlemen's Association, said that placing a dollar value on rangelands pollination services lends powerful support to these efforts.
“The value of grazing and other land stewardship practices of California’s ranchers is being increasingly acknowledged as not only a preferred land use, but also as an essential resource management tool,” said Sweet. “I hope this study is just the beginning of comparable findings that show how ranching is a critical – and multifaceted – element of California agriculture.”
The state’s rangelands have been decreasing steadily, as the foothills and oak-dotted grasslands can be highly desirable for residential development. California lost 105,000 acres of grazing lands to urbanization between 1990 and 2004, according to the state Department of Conservation. The California Oak Foundation projects that the state could lose another 750,000 acres by 2040.
Kremen said the findings suggest that if farmers paid ranchers to stay on the land and maintain the habitat, the farmers would be increasing their sources of pollination and developing critical diversification to support their agricultural practices.