Spread sheets to help you calculate loss
Information from Ben Faber, Soils and Water, Avocado and Minor Subtropicals Advisor
Information on how to care for fire damaged trees from Ben Faber, Soils and Water, Avocado and Minor Subtropicals Advisor
Information on fire ecology and fire safe landscaping for homeowners, developed by Sabrina Drill, Natural Resources Advisor
Information on fire science from UC experts. Includes information on how to make homes and other structures more fire re
Publications Available From University of California ANR Catalog
You can find the publications listed below at the University of California DANR Catalog site (In the ANR Search type fire) and order more than one publication at a time or you may click on one of the links below. if you purchase a priced publication enter the promotion code PRVEN56 at check-out. You'll receive a 10% discount on your order, and a portion of the sales will benefit local programs.
A Property Owner's Guide to Reducing Wildfire Threat - describes ways homeowners can reduce the threat of fire to their property. Cost $1.50
Home Landscaping for Fire - Incorporating fire safe concepts into your landscape is one of the most important ways you can help your home survive a wildfire. FREE
Landscaping Tips to Help Defend Your Home from Wildfire - You can have both a beautiful landscape and a defensible fire-safe zone. FREE
Recovering from Wildfire - discusses issues that family forest landowners should consider following a wildfire. Cost $5.00
WildFire: How Can We Live With It? (DVD) - This program contains general information about wildland fire in California. Cost $20.00
Companion Set: How Can We Live with Wildland Fire? (Publication and DVD) - What role does fire play in the natural cycle and what choices can we make about coping with wildland fire? Cost $27.50
How Can We Live with Wildland Fire? - What role does fire play in the natural cycle and what choices can we make about coping with wildland fire? Cost $10.00
sistant, developed by Steve Quarles, Statewide Wood Performance and Durability Advisor
Entomology, or the scientific study of insects, is not just rural--it's urban, too. Think bed...
Karey Windbiel-Rojas of the UC Statewide Integrated Pest Management Program (UC IPM), plans to wear this cockroach costume to the Bohart Museum of Entomology open house on Sunday, Nov. 18, when she will greet visitors and answer questions. An urban entomologist expert, she's the associate director for Urban and Community IPM who serves as the area urban IPM advisor for Yolo, Sacramento and Solano counties.
Pantry pests include booklice, pictured here in cornmeal. These nearly microscopic insects, Liposcelis bostrychophila, or "psocids" (pronounced "so kids"), are common pests in stored grains. They're usually unseen because they're about a millimeter long--about the size of a speck of dust--and are transparent to light brown in color. (Photo by Kathy Keatley Garvey)
Thanks for the rains that leach the soils of accumulated salts and bring on new fresh growth. Or maybe not. When we apply irrigation water with salts which with few exceptions we do in irrigated agriculture, salts accumulate in the soil. They accumulate in a certain pattern depending on the type of irrigation and soil type. There's a strong tendency for drip and microsprinklers to form a pattern of salt accumulation near the margins of the wetted patterns. This pattern is stronger with drip because the source point is always pushing a front outward from the emission point. This pattern occurs with microsprinklers, as well, although not as strongly. These patterns continue to form and accumulate as long as there is no rainfall to evenly push the salt down below the root zone. The longer the period of no rain, the larger the salt concentration at the margin.
So the way water moves is generally down. It moves in a wetting front drawn by gravity. It moves laterally too, because of the attraction water has for the soil particles. It will move laterally more in a clay soil than in a sandy soil because there are more particles in a clay soil than a sand (actually more surfaces that hold water). It also carries salt with it. Wherever the water moves, the salt moves. The more rain, the more salt is moved down. The more rain, the deeper the salt is pushed.
The problem with rain, is that if there is not enough, the salt tends to move laterally. In this wet soil solution, the salt is moving from where it is concentrated, to where there is a lower one. And if there isn't enough rain to move that salt down, it just moves back along the salt gradient, back to where the water first came from…….towards the roots. And that salt may be at such a high concentration that it can cause plant damage.
We talk about effective rainfall. This is usually about a quarter of an inch of rain. This is the amount of water to do more than just wet the dust, it's the amount to move water into the root zone. It is also moving salts into the root zone which can be a real problem. A good rain will do more than wet the dust, it will also move the salts out of harm's way in the root zone. The amount of rain necessary to do this is going to depend on the salt accumulated and the soil texture. The more salt, the more rain needed. The finer the texture, the more rain.
So there is no good cookbook, other than you need enough. And the first rains of the year, watch out. This is often when there is the highest salt accumulation and in the fall when we have the most irregular rains. Small rain amounts that can move salt into the root zone. A rule of thumb is a minimum of a good one inch rain event or combined rain events of two inches in a short period is needed to dissolve and move the salts out of the avocado root zone's top 18 inches. The more the better.
If there is not enough rain……………The solution !!!!!!!! Run the irrigation system to make sure there is enough to move that salt down.
Get ready to irrigate with the first rains if they are insufficient for adequate leaching.
Also get ready for the first smell of rain - petrichor.
Petrichor (/ˈpɛtrɪkɔːr/) is the earthy scent produced when rain falls on dry soil. The word is constructed from Greek petra (πέτρα), meaning "stone", and īchōr (ἰχώρ), the fluid that flows in the veins of the gods in Greek mythology.
The term was coined in 1964 by two Australian CSIRO researchers, Isabel Joy Bear and Richard G. Thomas, for an article in the journal Nature. In the article, the authors describe how the smell derives from an oil exuded by certain plants during dry periods, whereupon it is absorbed by clay-based soils and rocks. During rain, the oil is released into the air along with another compound, geosmin, a metabolic by-product of certain actinobacteria, which is emitted by wet soil, producing the distinctive scent; ozone may also be present if there is lightning. In a follow-up paper, Bear and Thomas (1965) showed that the oil retards seed germination and early plant growth.
In 2015, scientists from the Massachusetts Institute of Technology (MIT) used high-speed cameras to record how the scent moves into the air. The tests involved approximately 600 experiments on 28 different surfaces, including engineered materials and soil samples. When a raindrop lands on a porous surface, air from the pores forms small bubbles, which float to the surface and release aerosols. Such aerosols carry the scent, as well as bacteria and viruses from the soil. Raindrops that move at a slower rate tend to produce more aerosols; this serves as an explanation for why the petrichor is more common after light rains.
The human nose is extremely sensitive to geosmin and is able to detect it at concentrations as low as 5 parts per trillion. Some scientists believe that humans appreciate the rain scent because ancestors may have relied on rainy weather for survival.
avocado salt damage
For the last three decades, he's been searching for the "The Spirit of the Hive." That would be...
What's going on in the hive? World-renowned honey bee geneticist Robert Eugene “Rob” Page Jr., the 2018 recipient of the Thomas and Nina Leigh Distinguished Alumni Award, UC Davis Department of Entomology and Nematology, will speak on "In Search of the Spirit of the Hive: a 30-Year Quest"--at 4 p.m., Thursday, Nov. 29 in the International House, 10 College Park, Davis. (Photo by Kathy Keatley Garvey)
The recent outbreak in California of two devastating fires - the Woolsey Fire in Ventura and Los Angeles counties and the Camp Fire in Butte County - are being covered extensively by the news media. UC Agriculture and Natural Resources fire scientists provide a valuable service by making themselves available to share their expertise during these tragedies. Below are a sampling of recent fire stories with comments from UC ANR sources.
Why Wildfires Are Burning So Hot And Moving So Fast
(NPR) Kirk Siegler
…One recent study predicted several million homes built in the West are at immediate risk. Susie Kocher is a forester with the University of California's Cooperative Extension service here in the Sierra.
“We haven't caught up, and to retrofit our existing housing stock to fend off embers is a long-term, expensive proposition.”
These wind-driven fires often carry air and embers that land on a roof or get sucked into a vent long after the main wall of flames has passed through. In fact, that's when most homes actually burn in wildfires.
“Even areas like Paradise that have been inhabited for 140 years as more vulnerable than they used to be. And that's not because there's new development but because there's a new climate around the old community.”
And that brings us to one of the biggest factors: climate change. Droughts are longer and more severe. The snow is melting quicker. The fire seasons are longer if not year-round.
As wildfires grow deadlier, officials search for solutions
(Associated Press) Matthew Brown and Ellen Knickmeyer, Nov. 14
…"There are ... so many ways that can go wrong, in the warning, the modes of getting the message out, the confusion ... the traffic jams," said Max Moritz, a wildfire specialist with the University of California Cooperative Extension program.
As deadly urban wildfires become more common, officials should also consider establishing "local retreat zones, local safety zones" in communities where residents can ride out the deadly firestorms if escape seems impossible, Moritz said.
… In the mid-20th century, California ranchers burned hundreds of thousands of acres annually to manage their lands, said Lenya Quinn-Davidson, director of the Northern California Prescribed Fire Council.
That was phased out in the 1980s after California's fire management agency stepped in to take over the burns, and by the last decade, the amount of acreage being treated had dropped to less than 10,000 acres annually, Quinn-Davidson said.
Former agricultural land that rings many towns in the state became overgrown, even as housing developments pushed deeper into those rural areas. That was the situation in the Northern California town of Redding leading up to a fire that began in July and destroyed more than 1,000 homes. It was blamed for eight deaths.
"You get these growing cities pushing out - housing developments going right up into brush and wooded areas. One ignition on a bad day, and all that is threatened," Quinn-Davidson said. "These fires are tragic, and they're telling us this is urgent. We can't sit on our hands."
Trump and Brown stir up rhetoric on wildfires but overlook pressing problems
(LA Times) Bettina Boxall, Nov. 14
… Similarly, UC Berkeley fire scientist Scott Stephens said that although climate change is playing a role in wildfire growth, he worries that a focus on global warming can leave the public thinking that “there's really nothing to be done.”
In fact, he said, “Communities could still be better prepared.”
How Does California's Wildlife Cope With Massive Wildfires?
(Atlas Obscura) Anna Kusmer, Nov. 13
While many animals are indeed displaced by wildfires, it's important to note that fire is not wholly bad for landscapes in an ecological sense. In fact, many California ecosystems rely on fire to thrive. “Fire in the human sense can often be catastrophic, but it's not necessarily the same for animals,” says Greg Giusti, a retired University of California researcher and an expert on the relationship between wildfires and wildlife. He says California wildlife have evolved to respond to fires, and can even sometimes benefit from the disruption. “It's harsh out there, but you know these animals have evolved to survive in that hostile environment.”
There are a variety to survival tactics that California wildlife will use, says Giusti. For example, birds are easily able to fly away and are usually not impacted as long as fires don't occur during the spring when they are nesting and raising their offspring.
The Manmade Causes Of California's Endless Fire Season
(OnPoint) Meghna Chakrabarti, Nov 13
California's endless fire season. Whether it's climate change, development or forest management, we'll look at the causes — all manmade.
Scott McLean, deputy chief, chief of information for the California Department of Forestry and Fire Protection.
Ryan Lillis, reporter for the Sacramento Bee who has covered most of Northern California's fires for last 12 years. (@Ryan_Lillis)
J. Keith Gilless, professor of forest economics at University of California, Berkeley and chair of the California Board of Forestry and Fire Protection on Cal Fire's policy board.
Glen MacDonald, professor of geography at University of California, Los Angeles who has spent decades studying climate and the effects of wildfires. He and his family were among the hundreds of thousands of people who evacuated their homes because of the Woolsey Fire. (@GlenMMacDonald1)
California Must Better Prepare For The Inevitability Of Future Fires (reprint of The Conversation originally published in August)
(Pacific Standard) Max Moritz, Naomi Tague & Sarah Anderson, Nov 13
Wildfire has been an integral part of California ecosystems for centuries. Now, however, nearly a third of homes in California are in wildland urban interface areas where houses intermingling with wildlands and fire is a natural phenomenon. Just as Californians must live with earthquake risk, they must live with wildfires.
Forest management debate
(KTVU) Heather Holmes, Nov. 12
In a live interview, Bill Stewart, UC Cooperative Extension specialist at UC Berkeley, said,
“It was actually on the private land that we saw better performance in terms of being able to put out the fire quicker and a lot less smoke being produced. There is a package of vegetation management and fire suppression on private lands that have proved to be more effective than what's being used on federal land.
“What we found is about half the difference comes from the private land managers do more aggressive timber harvesting and some of that profit they spend to reduce the shrubs and fuels that are on the ground because they have that cashflow. They're protecting their long-term assets. The other half is CALFIRE is much more aggressive when it comes to fire suppression in forests or shrublands.
Trump's Misleading Claims About California's Fire ‘Mismanagement'
(New York Times) Kendra Pierre-Louis, Nov. 12
…Mr. Trump is suggesting that forest management played a role, but California's current wildfires aren't forest fires.
“These fires aren't even in forests,” said Max Moritz, a wildfire specialist at the University of California, Santa Barbara.
…“We have vulnerable housing stock already out there on the landscape. These are structures that were often built to building codes from earlier decades and they're not as fire resistant as they could be,” Dr. Moritz said. “This issue of where and how we built our homes has left us very exposed to home losses and fatalities like these.”
California's year-round wildfire threat: Why aren't communities doing more?
(SF Chronicle) Peter Fimrite and Kurtis Alexander Nov. 10,
…“To have a president come out and say it's all because of forest management is ridiculous. It completely ignores the dynamic of what's going on around us.” said LeRoy Westerling, a climate and fire scientist at UC Merced, who blamed the increasing number of fires on rising temperatures and more variable precipitation, leading to longer spells of dry weather.
…“It's like a tragic replay of last year, with strong winds in both Northern California and Southern California blowing fire,” said Max Moritz, a wildfire specialist at the Bren School at UC Santa Barbara, recalling the 2017 Wine Country fires and the Thomas Fire, which burned through Ventura and Santa Barbara counties in December.
…“We had a lot of discussion after the fires last year about the liability issue with utilities, but it's interesting to see what didn't happen,” Moritz said. “Nobody has talked about mapping neighborhoods and homes in fire-prone areas like they do in flood plain hazard zones, engineering resilience into communities, or building a little smarter.”
…Everybody agrees the situation is dire. Fire officials blame shorter winters, hotter temperatures and drier vegetation, but very little is being done to improve the situation, said Scott Stevens, a professor of fire science at UC Berkeley.
“There is an under-appreciation of fire risk in a lot of communities,” Stevens said. “It feels like we can do better at allowing local communities to access information, reduce their vulnerability and understand their vulnerability a little bit more.”
Stevens urged the creation of cooperative programs at his and other universities that would allow local government officials to collaborate with fire experts on safety planning.
California's most destructive wildfire should not have come as a surprise
(LA Times) Bettina Boxall and Paige St. John
…“We have these Santa Ana-like events happening in places that are appearing to catch people by surprise,” said Max Moritz, a cooperative extension wildfire specialist at UC Santa Barbara's Bren School. “But they shouldn't be catching people by surprise.”
“These are areas that have burned before,” he said. “And if we were to go back and do the wind mapping, we would find that at some intervals, these areas are prone to these north and northeasterly Santa Ana-like events.”
… “We have all kinds of tools to help us do this smarter, to build in a more sustainable way and to co-exist with fire,” he said. “But everybody throws up their hands and says, ‘Oh, all land-use planning is local. You can't tell people that they can't build there.' And the conversation stops right there.”