Invasive plants are defined by the Natural Resource Conservation Service (NRCS) as, “A plant that is both non-native and able to establish on many sites, grow quickly, and spread to the point of disrupting plant communities or ecosystems.” Depending on the location of your forest or oak woodland, this includes plants such as Scotch broom, cheatgrass, Tree-of-Heaven, pampas grass, and Himalayan blackberry. But for forest or oak woodland landowners who are looking to manage vegetation, there are also native plants that may be less desirable. The NRCS calls these either “Opportunistic native plants or weeds”. Opportunistic native plants, as defined by the NRCS, are able to take advantage of disturbance to the soil or existing vegetation to spread quickly and out-compete the other plants on the disturbed site, such as mountain misery. Weeds are defined as native plants that are not valued in the place where they are growing, or any plant that poses a major threat to agriculture and/or natural ecosystems such as Pacific poison oak.
Photo of Tree of Heaven with flowers
For any landowner, eradication of invasive plants is most effective when the infestation is small or localized. When an infestation covers large areas, you are more often than not, looking at controlling spread versus eradication.
Heather Morrison, a Registered Professional Forester (RPF) and licensed Pesticide Control Advisor, says, “Many times using herbicides in conjunction with other types of vegetation management, like mechanical or burning, can increase the efficacy of the treatments.”
We asked Heather about using herbicides to control invasive species and as a compliment to other vegetation management activities.
Q: Heather, how do you broach the subject of herbicide use with forest landowners?
A: I actually don't treat it any different than any other vegetation management scheme. It is one of the tools we can use and is most definitely a huge part of IPM (Integrated pest management). I present it as an option and if landowners are hesitance, we have a conversation about it. Herbicide isn't always the best choice and every situation is different.
Q: What are some examples where you have effectively used herbicides as a forest management tool?
A: One of the best uses is in shaded fuel breaks. Maintenance is key! People always seem to forget that the forest isn't static and it grows back, so these huge investments we make in establishing fuel breaks can be lost if we don't maintain them.
Another example is invasive plant suppression. Wildfires have been creating the perfect environment for increased spread of invasive plants like broom, pepper wood and stinkwort. The past two years I have been working with some forest landowners in the Glass Fire footprint to suppress French broom which was bad before the fire, and now is even worse. Because new plants take 2-3 years to produce viable seed, it has been a race to try and treat these areas before they release more seed. Broom plants produce thousands of seed per plant which remain viable in the soil for 70+ years!
Photo of scotch broom with flowers
Q: Are there situations where you would NOT recommend using herbicides?
A: Obviously if you are an organic farmer! Mostly what I find is you have to switch up the types of herbicides you use and the application method. Herbicides are very regulated and I like to remind people that we are applying usually only ounces per acre. This is compared to the same herbicides on the shelves where most likely consumers are not reading the label, wearing their Personal Protective Equipment (PPE) or applying the herbicide correctly.
Please note, the US Forest Service's “Forest Management Handbook” recommends that forest landowners who need to treat more than 1/10 acre with herbicides, should consult with an RPF, Certified Pesticide Applicator, or a licensed Pesticide Control Advisor.
For more information on Integrated Pest Management and invasive plant identification, please visit the UC IPM website.
UCCE forest advisor helps landowners, community groups determine best project options
As Californians prepare for another year of drought and an anticipated intense fire season, landowners and organizations across California have been working to reduce forest fuels – flammable woody material – that can endanger their properties and communities.
For many of them, however, their urgent efforts hit a sizable speed bump: a massive rulebook that describes, amid a thicket of other information, the permits required before people can treat or remove fuels – as well as a litany of attached requirements, restrictions and stipulations.
“The California Forest Practice Rules are 410 pages, in font size 6,” said Yana Valachovic, UC Cooperative Extension forest advisor for Humboldt and Del Norte counties and registered professional forester. “Trying to figure out what permit vehicles make sense in the rulebook is not easy even for the experienced professional forester.”
“We tried to create a system where all the permits are laid out side-by-side, and put in a decision tree framework to help make it easier,” said Valachovic, highlighting the publication's tables that break down the project goals and parameters a permit applicant should think about when weighing their choices.
Considerations include whether the project is pre- or post-wildfire, the location and dimensions of trees targeted for removal, the conditions of the site before and after the project, potential time limits, commercial options, and, crucially, budget constraints – given that the permitting process could comprise up to one-third of total project costs.
A primer for planning and preparation
Chris Curtis, the unit forester for CAL FIRE's Humboldt-Del Norte Unit, said that he and his colleagues are grateful for this new tool and plan to use it as an “over the counter” handout for community members. He added that the charts summarizing timber-harvesting regulations and possible funding sources are especially helpful.
“These give a landowner a starting place to sort through the many commercial timber harvesting documents and fuel-modification project funding source options available,” Curtis said. “A landowner is self-guided to a few options that will seem most appropriate, and this will facilitate a resource professional to assist that person in selecting the most appropriate permitting.”
The publication helps prepare the landowner or community entity (such as Resource Conservation Districts, Fire Safe Councils or other concerned groups) for the types of questions that might come up in preliminary planning conversations with a registered professional forester or RPF.
Just as a homeowner would talk with a contractor before tackling a construction project, landowners and community groups must consult with an RPF, Valachovic said. RPFs have the specialized knowledge of forest practice rules and regulations related to water, air quality and endangered species protections, and the license to file the permitting documents.
“That's what I do in my job: Landowners come to me and we start talking about goals and objectives,” she said. “We start thinking about potential timelines – which goals are short-term, which are long-term – and how we can put an operational plan together to help those landowners achieve their goals.”
Long-term projects, short-term actions
Among the many practical tips outlined in this guide, Valachovic emphasized one in particular: for landowners dipping their toes into fuel reduction for the first time, keep the project “simple and realistic.”
And while even smaller projects could be more expensive this year due to higher costs for gas, equipment and supplies, she said that now is still “a great time to plan,” as fuel-reduction projects can take months to develop and execute.
In the short-term, however, Valachovic stressed that the extremely dry conditions across the state make it imperative for Californians to harden their homes, manage the fuels (i.e., landscape plants, stored wood, tall grass, etc.) immediately adjacent to their homes, and devise and review family emergency plans; see UC ANR's Wildfire Preparation page for detailed information and resources.
“There are a lot of immediate actions that people can be doing this year to help mitigate their wildfire risks and prepare for the unexpected,” she said.
Empowering Property Owners to Conduct Prescribed Burns
Smoke billows over the forest like a slow-moving fog. Dried oak leaves singe, crackle and curl into ash. Neighbors, scientists and agency staffers rake the embers, directing the flames with calm, careful control. Ted Odell's grandson runs along his namesake trail, Henry's Hill, to adjust a hose.
This is Odell's property in Placer County, where five of his 11 acres are being burned by prescribed fire with assistance from Placer County Resource Conservation District, UC Davis researchers and others.
He feels good knowing that this gentle fire will bring ecological benefits to his property, which was just 1 mile from the River Fire's evacuation zone last summer. But he's clear about his objective.
“My goal is very simple: Reduce fire threat,” he said. “I'm hoping this is a cost-effective way to manage the land. I can't solve climate change, but I can make my property more resilient.”
California's wildfire problem is no secret. Getting “good fire” on the ground, such as through prescribed fires and cultural burning practices, is a key tool toward addressing it. But landowners need help learning how to safely conduct burns on their properties, while also securing the necessary permits for burns to take place.
Increasingly, state and local agencies, as well as neighborhood burn associations, are creating opportunities to help landowners become a bigger part of wildfire resilience efforts.
“The burn at Odell's is an example of the kind of project the state hopes to expand, and which ecologists think is an important aspect of adapting to climate change in California,” said Andrew Latimer, a professor in the UC Davis plant sciences department.
Odell '78, a graduate of UC Davis' College of Engineering, has grazed sheep and goats, limbed up trees, and tried other fire-protection strategies, but he struggled to manage the property's fire risk.
He connected with UC Davis fire ecologist Hugh Safford after hearing him speak at a UC Davis virtual series about wildfire. When Safford visited his property, he advised Odell to treat it with prescribed fire and connected him with the Placer County RCD and its Cal Fire-funded project, Prescribed Burning on Private Lands.
“How do we actually put fire on the ground on half a million acres in California?” said Placer County RCD project coordinator Cordi Craig, referring to the state's shared stewardship agreement with the U.S. Forest Service. “Our goal is to empower half a million landowners to burn 1 acre. We're trying to give private landowners the knowledge, skills and confidence to put fire on the ground and use good fire as a forest stewardship tool.”
Community wildfire resilience
It's a springlike day in February when Odell's burn takes place. Miner's lettuce and wild hyacinth are already emerging from the ground, a reminder of the region's rising temperatures.
Just before Odell lights the first flame, a neighboring family walks over the hill. They include grandparents and a mother holding her baby. Some neighbors had their own property treated with prescribed fire the previous week, and they've come to observe and learn from those here, who include Craig, retired Cal Fire battalion chief Chris Paulus and several fire scientists from Safford's lab in the UC Davis environmental science and policy department.
“We have to reestablish our burn culture, that knowledge, and work as neighbors to do a lot of good,” Paulus tells the group, noting that Indigenous people routinely burned this land for acorn production and other benefits before European settlers arrived.
Monitoring the prescription
UC Davis is monitoring the results of this and several other prescribed burns across the state — ranging from Yosemite to Klamath national forests and throughout the Sierra Nevada — as part of the California Prescribed Fire Monitoring Program, in partnership with Cal Fire and the California Air Resources Board.
“Landowners are small, but they add up, and together they form an important base,” said John Williams, a UC Davis project scientist who leads the monitoring program. “Our mandate is to see what effects prescribed burns have and to use the data we collect to help land managers and owners achieve their ecological restoration and fuels reduction goals.”
Now in its third year, the program monitors nearly 600 plots across more than 25 sites in California. Once a site is identified for burning, scientists and field crews conduct vegetation surveys, and measure things like forest structure, downed woody debris and leaf litter. They record fire behavior during the burn and then return twice — in the immediate weeks after the fire and a year later — to collect post-fire data and learn how well the prescribed burn objectives were met.
The data they collect will become part of a database that forest agencies and even landowners like Odell could use to have a better idea of how a prescribed burn might behave at a property. Such a database could also help foresters prioritize areas for treatment, restoration, reseeding and other efforts.
Enormous tasks, reasons for hope
Williams said people sometimes think prescribed burns are a silver bullet for managing wildfire. But he said the task ahead is enormous.
“To my knowledge, the most we as a state have burned in a year is around 120,000 acres,” he said. “There are roughly 30 million acres that are one or more fire cycles behind because of suppression. So there's a lot of catching up to do.”
That said, he sees cause for optimism for several reasons:
Local, state and federal agencies that were long dominated by fire-suppression strategies are now expanding and promoting prescribed burning and other treatments, and putting money behind it. It may not be happening at the scale and speed we'd like to see, but it's happening.
Prescribed fires — and the smoke that accompanies them — are becoming more socially acceptable to residents, most of whom have now witnessed or experienced the impacts of high-severity wildfire.
Cultural burning and Indigenous practices that use fire not just as means to avoid worse fire, but to restore the land, are being included and acknowledged in state and national forest plans. “There's now much more language and directives to build on these traditions that we [non-Native people], at best ignored and at worst suppressed and tried to stomp out,” Williams said.
More landowners are forging connections to bring fire back to their properties, as seen by keen interest in Prescribed Fire Training Exchanges (TREX) events, and other outreach efforts. Prescribed burn associations, such as those in Humboldt and Nevada counties, are also experiencing broader appeal. Williams said that in divisive times, prescribed burns are one event that is bipartisan.
“You can't identify a prescribed burner by their political party,” he said. “These associations are bringing neighbors and communities together.”
For Odell, he's hopeful not to need as much assistance the next time he needs to treat his land with fire.
“Am I comfortable? Not yet,” he said. “But we do this to get a sense of it. Part of it is just being around it and seeing it.”
Once outlawed, cultural burns can save our forests from uncontrollable wildfire
In the past several years, California has endured the most extreme fires in its recorded history.
2018's Camp Fire grew into the state's deadliest and most destructive fire on record, devastating the towns of Paradise and Concow. Last year the state suffered the Dixie Fire, raging for months through five Northern California counties on its way to becoming the single-largest blaze in state history.
These deadly infernos are stark evidence of how vulnerable California's communities and forests have become in the era of climate change. But warmer, dryer forests aren't the only factor behind these so-called mega fires. Ironically, it is a lack of fire that is also playing a major role.
Two hundred years ago, someone walking through Yosemite would not have seen the densely packed forests we now associate with the Sierra Nevada.
They would have passed through broad meadows and perhaps have even been drawn to comment, as the Spanish did, on how the land appeared like a “well-tended garden.”
In fact, that is exactly what Spaniards were seeing: Indigenous people native to Yosemite and other parts of the world for millennia have used fire to promote healthy forests. Today, the wisdom of that approach is seen as one of the keys to unraveling the deadly cycle of California wildfires. (Video about Yosemite National Park)
Using fire to help forests flourish
It's easy to assume that the impenetrable forests we associate with the mountains of California have always been there. Many of the popular images of Yosemite, for example, were taken decades after federal agencies moved to suppress fires in the region and removed native tribes.
Ask the Honorable Ron W. Goode, Tribal Chairman of the North Fork Mono Tribe, what's missing from the land and he will tell you it's fire.
It may be a contentious subject, especially given California's recent traumatic wildfires. “But I need to talk to you about fire,” Goode says.
“Many of the bushes that we're now burning haven't actually been burned for about one hundred and twenty years,” Goode said while conducting a burn on the Jack Kirk estate in Mariposa, California. “And they're crying. They want fire, they want to be restored.”
“When you talk to different native people from the Yosemite area, they talk about how it used to look when fire was used as a management tool,” says UC Davis professor of Native American Studies Beth Rose Middleton Manning. Her classes have worked alongside Goode and members of other local tribes to help carry out traditional Indigenous burns. “The way valleys are now being encroached upon by conifers and other species in areas that were once open.”
The landscapes tribes in California cultivated were diverse, including foothills, woodlands and forest. Goode describes how, as a result of Indigenous land management, Spaniards were able to travel for over 60 miles under a canopy of mostly water oaks, a shade tree that produces abundant acorns, and how early Euro Americans found wide open pathways into Yosemite.
But early European settlers who set foot in California saw tribes setting fire to the land and regarded it as primitive. Strangers to the ecosystem and fire's role within it, they suppressed the practice. In 1850, California passed the Act for the Government and Protection of Indians, which outlawed intentional burning in the newly formed state. One early U.S. forest ranger suggested people who set fire to the land should be shot.
Federal and state governments radically transformed the land in other ways as well. In many instances, tribes were forced off the lands they had been carefully maintaining. Forests were extensively logged, then replanted in dense groves, further shifting delicate balances between trees and open areas, and creating the kind of closely packed forests that can fuel massive, uncontrolled wildfires.
Goode estimates that the California canopy is now twice as dense, or more, in places that have been missing fire. “When the Indian was on the land, the canopy was 40 percent or less open,” he says. In that open space, a variety of plants, bushes, and smaller trees, like oak trees, were able to grow, as did plants still used today by native tribes for food, medicinal or cultural purposes. These varied landscapes were more resilient to fire; in today's forests, once the crowns of the trees catch fire, a blaze spreads rapidly, using the tree canopy as a kind of deadly highway.
Credit: Bioneers Beth Rose Middleton Manning
These tall trees, planted close together, compete with one another for sunlight and water, and prevent smaller plants below from thriving. Stressed by drought and climate change, they are vulnerable to parasitic attacks. Bark beetles have now killed as much as 5 percent of the forest in the western United States, scientists estimate. These dead trees are more fuel for wildfires, helping them spin out of control.
“When everything's a mess and dry and needs brushing, needs clearing, then only the big trees are the ones that are sucking up water,” Goode says. “They can reach down two meters, but cultural plants can only go down about a meter for water. Beyond that, they're out of water. That's when you begin to see parasites attack the bushes and the plants.
“Who grows a garden like that?” Goode asks.
“That's why the need is to come in and put fire on the land.”
Goode has been practicing what is known as cultural burning for nearly 30 years. Cultural burns are a form of land management passed down by Indigenous tribes over thousands of years. It is called cultural burning not only because of its spiritual and cultural importance to Indigenous communities, but because the burns are designed to cultivate the biodiverse, sustainable growth that make landscapes more resilient. Goode shares the importance of the practice with educational and government institutions and teaches others, including students of UC Davis professor Middleton Manning, how to use fire to restore the land.
In response to a foundational 1963 report led by UC Berkeley conservationist A. Starker Leopold, the U.S. National Park Service changed its policy in 1968 to allow lightning fires to burn within special fire management zones — usually remote regions at high elevations — where danger to human settlements was low. Forestry and park services have also shifted their approaches to include strategic use of fire to thin vulnerable areas. This practice, known as prescribed burning, is performed by fire experts under certain conditions in select areas.
Prescribed burns versus cultural burns
But there are important differences in philosophy and execution between prescribed burns and cultural burning in their approach to the land, Goode says.
Agencies tend to focus on acreage and fuel reduction, relying upon natural features or previous fires to control potential spread. Forestry technicians may prioritize large-scale pile burning, for example, then leave when it is done.
Indigenous cultural burns focus on what needs to be burned to revitalize the land with the intent of returning to make use of it again. Traditional baby baskets of the Yurok and Karuk Northern California tribes, for instance, are made from hazelnut shrub stems that are collected after fires. Only those types of stems are straight and strong enough to create the baskets. But in order to collect them, hazelnut shrubs must be burned, a step many agencies do not currently take.
Indigenous preparation of land for a burn can also involve promoting oak trees in place of pines, for example, creating a new food source for animals and people alike. The ecological and spiritual importance of cultural burns is written into a North Fork Mono creation story — how the Inchworm was able to retrieve the Falcon caught on a high rock by going up the rising water table created by fires put on the land by the Mono.
“Cultural burning comes back to what we are burning for, and it's not burning for acres,” Goode says. “We're burning to restore the land, restore the resources, restore water. Bring it back to where it can reproduce on its own.”
Credit: Kat Kerlin/UC Davis. Julie Dick Tex of the Western Mono tribe collects sourberry branches for basket making in Mariposa in 2020. Read more about Tex, sourberry basketry and UC Davis' engagement with cultural burns here.
A generational approach to burns
Another important difference between prescribed burns and cultural burns is their approach to time. The North Fork Mono Tribe puts fire on the land in a decades-long cycle. “We're burning minimally three times in 10 years,” Goode says. “Then the next 20 years, you're only going to need to burn once. That's what we call a 30-year cycle.” During the cycle, older people like Goode, now 71, train younger people on how to perform the burns correctly. Each burner performs this cycle of training and implementation and passes it onto the next.
“We thrive on the land, not survive,” Goode says. “Indians didn't ‘survive.' We look to our grandchildren's grandchildren, seven generations, basically 120 years down the road, that's where we look. So the decisions that we make and our practices that we do today need to affect generations down the road.”
This way of thinking and training others is difficult to translate into agency land management environments that are constrained by budget cycles, employee retention and other red tape issues that constrain the tribes themselves.
Nature, on the other hand, doesn't wait for a permit — and so the many varieties of berries, brush, buds and trees that each play a role in a forest's health languish, sometimes with deadly consequences.
University of California Cooperative Extension fire advisor and Northern California Prescribed Fire Council director Lenya N. Quinn-Davidson suggests we embrace this approach to fire.
“There is so much to learn from cultural practitioners — not just about traditions and techniques, but also about stewardship and connectedness,” she says. “Fire is a reflection of culture, and the kinds of fires we've been experiencing in California are a projection of our own disconnection and imbalance. It's time to reclaim the balance, rebuild the relationship. Cultural practitioners can help show us how.”
“Tribal members describe intensive landscape stewardship that they were engaged in in the past, which included low intensity burning, coppicing or trimming plants. And all of the work that they did had positive effects on opening up the forest, raising the water table,” Middleton Manning says. “There was no downside.”
A recent UC Berkeley study of Yosemite's Illilouette Creek Basin — a 60-square-mile area where lightning-created fires have been allowed to take their course over the past half-century — also speaks to fire's healing effects. Here the landscape looks something like it may have looked 200 years ago: A mixture of grassland, shrubland and meadow filled with abundant wildflowers and boosted plant and pollinator diversity.
“I think climate change is no more than 20 to 25 percent responsible for our current fire problems in the state, and most of it is due to the way our forests are,” said senior study author Scott Stephens in a recent interview. “Illilouette Basin is one of the few places in the state that actually provides that information, because there is no evidence of changes in fire size or in the severity of fires that burn in the area. So, even though the ecosystem is being impacted by climate change, its feedbacks are so profound that it's not changing the fire regime at all.”
Setting up the structure to support the practice of cultural burns in a 21st century climate of catastrophic fires is tricky, however. Land agreements can be tenuous, and state and federal agencies are still learning how to delegate stewardship of the land, and its burning, to the tribes that originally lived on it.
“The Forest Service or another agency may say, ‘OK, we hear you. This plant needs burning in order to be healthy so you can continue your tradition,'” Middleton Manning says. “‘But we can't let you burn because you don't have the certification. So our people have to burn and you can watch.' I think that is enormously frustrating for Indigenous people. And I know Ron Goode and others have advocated strongly for recognizing Indigenous expertise in Indigenous knowledge.”
But some positive changes have been made. A new California law, effective January 1, 2022, has affirmed the right to cultural burns, reducing the layers of liability and permission needed to set “good fire” on the land.
Yosemite itself is in the process of welcoming a return to cultural fire under the oaks in the Valley, Middleton Manning notes, led in part by National Park Service cultural ecologist Irene Vasquez, a UC Santa Cruz alum and Southern Sierra Miwuk and Paiute tribal member.
And there's a lot of really exciting stewardship and restoration projects happening on lands held or managed by native land trusts, Middleton Manning says, encompassing practices from pile burning to replanting native seeds, that bring together several generations of tribal communities.
These people, and other lifeforms essential to the ecological balance, can return after the cultural burns and enjoy the fruits of their work.
During a cultural burn shared with one of Middleton Manning's classes, Goode, tribal members and students burned three-leaf sumac that had been attacked by lichen and was dying. In need of new growth, it was unable to produce sticks for basketry or berries for food and medicine.
“When we burn it, a new crop will start to come up in a few months,” Goode said. “We should even be able to harvest by July or August from the very bush that we're burning in the back.”
And so they did — fulfilling a cycle that has shaped California for thousands of years.
Forests in the Sierra Nevada and southern Cascade Range are being stressed by many factors that put them at risk. High-severity wildfire, drought stress, insect outbreaks, disease, and a backdrop of changing climate are a few. A significant portion of Sierra Nevada and southern Cascade forests are owned and managed as small parcels (10 to 100 acres) by nonindustrial private landowners. To assist these landowners, CAL FIRE and the U.S. Forest Service Pacific Southwest Research Station have recently released the ‘Forest Management Handbook for Small Parcel Landowners.' This step by step guide is an additional resource designed to help small, private forest landowners gather the information needed to begin developing a California Cooperative Forest Management Plan, including determining what, if any, management actions need to be done, and where to obtain technical and financial support.
“California's small private landowners need access to tools and technical assistance to help them manage their forest lands to maintain forest health,” said Stewart McMorrow, CAL FIRE's wildfire resilience staff chief. “Forest landowners do not always have the knowledge or skills to get started with a management plan, which is why the handbook was created.”
Four important areas are addressed in the handbook including:
Defining your forest management objectives;
Assessing your current forest conditions;
Recognizing threats to the health of your forest; and
Evaluating possible treatment options.
A California Cooperative Forest Management Plan (CCFMP) can be simple or complex based on a landowner's management goals and objectives. For those ‘do-it-yourself' landowners, the handbook provides worksheets that can help guide you through basic management activities. For landowners with larger parcels, multiple goals, complex management activities, and a desire to participate in cost-share programs (i.e. CFIP or EQIP), a Registered Professional Forester (RPF) is required to complete and submit your management plan. However, the handbook can be used as an important first step to assist landowners and guide conversations with their RPFs.
For landowners who would like more assistance in understanding and developing a California Cooperative Forest Management Plan, consider signing up for an upcoming Forest Stewardship Workshop series hosted by the University of California Agriculture and Natural Resources. The nine-week online workshop covers:
Forest management objectives and planning
Forest health, insects and disease
Forest and fire ecology, wildlife, watersheds
Fuels reduction and forest resource marketing
Project development & permitting
Getting professional help and cost-share opportunities
The in-person field day covers silviculture, forest inventory and mapping activities. Participants who complete the workshop will be eligible for a free site visit with a California Registered Professional Forester.