Authors: Alli Fish and Niki Mazaroli, Strategy Research Science

Silvopasture is the intentional and intensive combination of trees, forage, and livestock on the same piece of land. The applicability and potential benefit of silvopasture to both ranchlands and orchards – two agricultural landscapes that dominate the region – adds to its promise as a climate-smart agriculture practice in Santa Barbara and Ventura Counties.

Over 80% of land in Ventura County and over 90% in Santa Barbara County is either being grazed or has the potential to be grazed. [1] And while silvopasture systems will not be suitable for all of the nearly 2 million acres of rangeland, silvopasture has great potential to support both livestock production and ecological health in the region.

What qualifies as silvopasture?

To put it simply, there are two approaches to establishing a silvopasture system: adding trees to pasture or adding animals to tree systems. Tree systems can include natural forests, timber plantations, and orchards.A key piece to the definition of silvopasture according to the USDA is that the combination of pasture, trees, and animals must be intentional and managed as a system, as opposed to “individual practices that occur coincidentally together or managed independently.” [2]

A key piece to managing a productive silvopasture system is rotational grazing, a livestock and pasture management practice that has been shown to greatly improve soil health when implemented correctly. Rotational grazing is also essential to maintaining the health of the pasture and minimizing damage to trees, especially young trees. Once trees are established and above browsing height, which varies depending on the grazing animals, this is less of a factor. However, the combination of animal and edible tree crops triggers important food safety regulations that must be considered early on in the design of any silvopasture system. (See “Regulations” below.)

Example of silvopasture. Photo credit National Agroforestry Center.

What are the potential benefits of silvopasture as a climate-smart agriculture practice?

The NRCS recognizes silvopasture as a multi-purpose conservation practice that can:

• Provide forage, shade, and/or shelter for livestock.
• Improve the productivity and health of trees/shrubs and forages.
• Improve water quality.
• Reduce erosion.
• Enhance wildlife habitat.
• Improve biological diversity.
• Improve soil quality.
• Increase carbon sequestration and storage.
• Provide habitat for beneficial organisms and pollinators. [3]

In terms of a producer's economic bottom line, silvopasture can be a way of diversifying revenue. For example, the shorter-term income from grazing livestock can buffer or offset the upfront cost of establishing trees and shrubs onto existing pasture. [4]

Cattle finding shade through silvopasture practices. Photo credit David Hazen on Flickr

Challenges and considerations

While formulaic in its definition, the actual practice of silvopasture is extremely site-specific, like most things in farming and ranching. The limitations of the land and the market opportunities available will inform the desired and required tree crop, forage, and livestock of the system.

And while there is consensus on the potential benefits of silvopasture, there isn't one single model – one combination of trees, forage, and livestock – that can inform all silvopasture operations.

Instead, there are many factors to consider when planning a silvopasture system, and most of them are interrelated:

• Regulations: Regulations are particularly tricky for silvopasture systems producing edible tree crops (i.e. fruit and nut trees). To comply with the GAP and NOP standards, raw manure cannot be applied 90 day before harvest of crops not in contact with the ground (i.e. many fruits crops) and 120 day for crops in contact with the ground (i.e. all row crops, and some tree crops). Farms with annual revenue greater than $500,000 and/or that sell majority of product beyond 275 miles must also comply with additional regulations as part of the Food Safety Modernization Act (FSMA). [5] Note that some packinghouses have agreed to only take fruit that is GAP certified. It is important to understand where any edible crops you will be producing will be sold and any associated food safety requirements before beginning or converting to silvopasture.
• Management skills and labor: Livestock producers must learn to manage trees, and, conversely, growers must learn to care for livestock. Additional infrastructure (potentially lots of fencing!) and labor to start up and maintain a rotational grazing system.
• Tree selection and system design: Depending on your existing operation and goals, you might prioritize fast growing trees that produce forage and aren't as delicate to livestock damage; or you might select tree crops or timber trees that are slower growing but have the potential to generate more revenue over time. Whether or not you own your land and, if you lease land, the terms of your lease may also influence the trees you chose to plant and your silvopasture plan overall.
• Source of forage: Will the trees and shrubs be a source of the forage or another crop to sell? Or both! Unharvested fruit and nuts can be consumed by livestock and a source of increased soil fertility when deposited as manure.

 Are you practicing silvopasture in Santa Barbara or Ventura counties? If so, let us know! We are interested in learning more about the opportunities and challenges that local producers face when implementing and managing these systems. 

 If you have plans for integrating silvopasture on your farm to help meet your soil health goals, consider applying for funding through the California Department of Food and Agriculture's Healthy Soils Program. Grant applications are expected to open early February 2020, you can stay up to date with email notifications and by checking the website: https://www.cdfa.ca.gov/oefi/healthysoils/. If you have questions or would like technical assistance on the grant process, please contact your local technical assistance provider at http://ciwr.ucanr.edu/Programs/ClimateSmartAg/TechnicalAssistanceProviders/. 

Plantings of trees as an example of silvopasture. Photo credit National Agroforestry Center.

Citations:

[1] California Gap Analysis Project “GAP”: California Fish and Wildlife Service and UCSB

[2] Brantly, S. What Silvopasture?—Working Trees. USDA National Agroforestry Center; 2013. Available online:https://www.fs.usda.gov/nac/assets/documents/workingtrees/infosheets/WhatIsSilvopastureInfoSheetMay2013.pdf. Accessed on 10 Dec 2019.

[3] USDA NRCS. Silvopasture (Code 381) Conservation Practice Standard. Pennsylvania. 2016. Available online: https://www.nrcs.usda.gov/wps/PA_NRCSConsumption/download?cid=stelprdb1255015&ext=pdf. Accessed on 1 Dec 2019.

[4] USDA NAC. Silvopasture. USDA National Agroforestry Center. 2019. Available online: https://www.fs.usda.gov/nac/practices/silvopasture.php. Accessed on 1 Dec 2019. 

[5] Gabriel, S. Silvopasture: A Guide to Managing Grazing Animals, Forage Crops, and Trees in a Temperate Farm Ecosystem. Chelsea Green Publishing, 2018.

As I have mentioned in my previous blogs, I have a certain affinity for cover crops. Mostly it is because I see enormous potential to increase the soil health and climate resiliency in Ventura County agriculture by incorporating cover crops. To shed some light on suitable cover crops for Ventura County, I seeded a cover crop demonstration at UCANR's Hansen Agricultural Research and Education Center in Santa Paula. On December 3^rd, farmers, ranchers, gardeners, and community educators were invited to attend a Cover Crop Field Day to learn about different cover crops, compost, and the Healthy Soils Grant opportunity.

The field day attracted growers of all kinds from throughout the county. In attendance were orchard owners, berry and vegetable growers, ranchers, urban farmers, and enthusiastic gardeners, totaling over 100 people! Who knew so many people wanted to learn about my favorite topic?

The cover crop demonstration showcases cover crops in accordance to their functional category: biomass builders, pollinator habitat, low stature, and mustard. Mixes are seeded in long plots with their individual components seeded in smaller plots alongside. This allows for the chance to see the differences between mixes versus single species.

UCANR's Shulamit Shroder explaining the Biomass Builder category. Photo credit: Rose Hayden-Smith.

Beardless wheat, one of the components of Kamprath Seed Company's High Carbon Mix.

UCCE Advisor Oleg Daugovish explaining benefits of low profile cover crops. Photo credit Rose Hayden-Smith.

Pollinator Habitat Mix by Xerces. Provided by S&S Seed.

Ventura County RCD's Jamie Whiteford talking about pollinator and beneficial habitat covers. Photo credit Rose Hayden-Smith.

UCCE Ventura County Director Annemiek Schilder and Research Associate Dee Vega showcasing composting for healthy soils. Photo credit Rose Hayden-Smith.

I would like to extend a deep thanks to CDFA, UCANR, the Hansen Agricultural Research and Education Center, Kamprath Seed, and S&S Seed for their generous donation of time, seed, and resources to make this demonstration and field day possible.

Want to know more about what we are up to around the state? Check out this recent press release by UCANR about the Climate Smart Agriculture team.

Cover Crop Demonstration. Photo taken October 1 2019.

Climate smart agriculture encompasses management practices that increase soil carbon sequestration, reduce greenhouse gas emissions, improve yields and efficiencies, and promotes climate resilience. The California Department of Food and Agriculture (CDFA) supports three funding opportunities in climate smart agriculture: the Healthy Soils Program, the State Water Efficiency & Enhancement Program, and the Alternative Manure Management Program.

 In a collaborative partnership, CDFA and UC Agriculture and Natural Resources have teamed up to support 10 community education specialists throughout the state to provide technical assistance and outreach for the climate smart agriculture programs.

Alder Springs Vineyard in May 2019

Located in Laytonville, CA, 150 miles North of San Francisco and 12 miles from the Pacific Ocean, sits Alder Springs Vineyard. This remarkable piece of land is home to approximately 140 acres of wine grape vines ranging in cultivars and management practices. To a UC Climate-Smart Ag Specialist, speaking to owner/manager Stuart Bewley and visiting this land is always an informative and inspirational experience. In my work with the CDFA Healthy Soils Program, and later with the North Coast Soil Health Hub, I've had a chance to meet with Stuart on several occasions, and recently got to sit down and record a few of his thoughts on the matter of ecological land stewardship.

A scientist at heart, Stuart took viticulture courses at UC Davis and traveled the world, meeting with other vineyard managers, industry contacts, consultants and experts, to better understand how to produce quality grapes.

“We're in the vineyard business, and in order to attract and keep clients, we have to make great wine. Most of our clients are relatively small, so they have a competitive disadvantage… a smaller company lacks the competitiveness of an army of salespeople being able to twist the arms of distributors, they have to compete on quality. And that quality has to be superior. The wines have to just be extraordinary. And in order for those wines to be extraordinary, their grapes have to be extraordinary. And I believe, in order to keep my clients competitive, I have to grow extraordinary grapes.”-SB

Because of this, Stuart is constantly experimenting with management strategies, tailoring each varietal to their unique management needs. But beyond business, he has a strong pull to make his production more ecologically sustainable for a number of reasons. Increasing Carbon in his soils and reducing herbicide use were the reasons I first received a phone call from Stuart, just a few weeks after joining the UCCE office in Ukiah. 

Stuart in the Vineyard. Under several inches of snow lays another several inches of mulch.

This was early February 2019, and Stuart was interested in applying for a Healthy Soils Program award. His project idea was to apply heavy bands of compost and mulch under his vines to suppress weeds while reducing Nitrogen lockup and erosion, inoculating the soil with microorganisms, and increasing soil Carbon. 

“With more and more evidence that Round-Up is carcinogenic, our winery clients are starting to demand we use another method of weed control under-vine. Not wanting to continue to put ourselves, our labor, our customers, or our ecosystems in harm's way, we feel that it is time to change our methods. The only other method used by most Organic or Biodynamic growers is tilling.  This method releases carbon into the atmosphere and reduces the organic matter in the soil.  We are on hillsides with year-round class 1 streams near our vineyards. (These streams are spawning grounds for Steel Head, King Salmon, and Coho Salmon.)  We need a method of under-vine weed control that protects the soil from erosion. Through a small experiment on another parcel, we were able to determine that a one-time application of a 3" mulch layer is enough to suppress weeds and reduce soil erosion for up to 3 years. A thick band of compost under the mulch was shown to add enough available Nitrogen to maintain vine vigor. Together they proved to be an effective practice for suppressing weeds with the added benefit of soil protection from erosion and ultraviolet light. We would also like to measure the effects of these practices on the structure and quality of soil organic matter, the reduction of GHG emissions, and the capacity of soil Carbon sequestration.” -Excerpt from the Alder Springs HSP application (unsubmitted)

Unfortunately, due to the strict implementation requirements of the HSP Incentives Program, we weren't able to submit an application for the last HSP round in March of 2019. Based on their calculations and guidelines of their scientific committee, HSP requires farmers implementing compost and mulch as their project to apply both once a year for three years, instead of the desired one-time application. This requirement was beyond the realms of possibility, because the cost of the project skyrocketed well beyond the max award amount of $75k when tripled, even at the smaller scale of approx. 30 acres. We considered a HSP Demonstration Project, which allows for experimental trials at different application rates, but with the lack of time and resources, the scope of the project unfortunately became bigger than we could chew. Sadly, we had to pull out of the application process at the last moment, with the hopes that we could fine tune a project by the next round in early 2020. The silver lining to this is, upon deciding to go through with the project without CDFA funding, Stuart discovered a large challenge that would have made it nearly impossible to pull off, even with a one-time application of mulch:

“I got too ambitious last time. I should have been simpler and just done a compost application grant. You know what's interesting is I ended up doing a certain amount of this on my own, and I've learned a few things: Putting the mulch on, even though I still like the idea of the program, the amount of time and expense of doing that is astronomical, on any kind of a volume basis. Just because there's so much material you're putting out. Even though the woodchips don't break down very quickly, and they last quite a few years, there's a lot of woodchips out there and the only equipment we can get out there is relatively small equipment. And the number of loads was just massive, and the amount of time it took was incredible. I calculated 1 full time guy, I couldn't even do it in a year if he worked 50 hours a week. I was going, ‘wow I can't put that kind of commitment into this.'”- SB

The thick band of woodchip mulch can suppress weeds for up to 3 years. Underneath is a thick band of compost.

Pulling off the grandiose scope of work commitment with these grant agreements is one potential pitfall, I've discovered from working on these grants this year. Several of the HSP award winners I've worked with are operating with a sort of shell-shock as they are starting their projects and fully realizing what they signed up for. Scope of work revisions are possible, but with the winter season approaching and the year 1 deadline looming, getting out there sooner rather than later is key. This is advice I will be preaching in the following rounds: go for what you realistically want to do on your land with just a few months' notice. It's better if you consider this opportunity as spending your own time and money instead of getting piles of free money from the government. A small project may be funded more readily than an ambitious project that will need to be revised when it's understood you can't actually pull it off. 

As for Stuart, he's got another project in mind for this next round of funding: undervine cover crops. He's already started experimenting on a small scale on another parcel.

“I apply compost and then I put down clover seed and just sort of rake it in. Then it pops out and it only grows about 4-5in tall, which is no problem. And then I bought a Fischer Twister, which is an Italian machine that mows under the vine. I had done about 3-4 acres and it worked fantastically. It eliminates tilling, it eliminates herbicide, it uses compost, and it also sequesters Carbon through the growing plant material, and it totally prevents and eliminates erosion, and it also builds bacteria and fungi (particularly fungi for vineyards) in the soil. Any volunteer weeds that grow taller than clover get mowed out.” -SB

Clover growing undervine. In addition to clover, he uses native sedge grasses and an annual cover crop mix.

 

He admitted this experiment does work better on older vines, with no noticeable reduction to vine vigor and without a need to increase irrigation. In contrast, younger vines still require twice as much watering as their roots compete for available soil moisture. But the benefit of reducing erosion on the hillsides makes it a valuable management practice regardless.

“Where I've got grass or cover crop only in the [tractor rows], after 20 years it's higher than the [vine]row itself. The [vine]row is sinking. That's probably the result of erosion or it's just naturally losing Carbon and we're not reapplying Carbon. Whereas on mowing, I probably have to mow 4-5 times a season. So not only do I have plants that are growing and have root mass, but I'm also adding all their cuttings to the same area 5x a year. Over 20 years the tractor rows are building up and the vine rows are sinking. So now the vine rows are becoming a stream bed, and we're seeing even more erosion.” -SB

Stuart intends on applying for the next round of HSP Incentives Program awards for his undervine cover crop experiment, but he's also got something else on his mind that hasn't made it onto the HSP list of eligible management practices: biochar.  

“We have massive numbers of acres of forest that are tremendously over-populated with underbrush. So my forest, and everyone else's forests, are tinderboxes waiting to explode on an October afternoon with low humidity and high winds. So instead of sequestering Carbon, we're releasing it into the air in massive forest fires. If you were to take a substantial percent of that Carbon, and chip them up and turn them into biochar, not only would you be able to prevent forest fires, you would be able to sequester it in agricultural soils for a thousand years. Biochar changes the whole structure of the soil. It absorbs a tremendous amount of moisture, and a small piece of biochar can be the home for millions of bacteria and fungi. Because they absorb and hold so much moisture, you can create an environment where soil biology functions properly, and it sequesters moisture for the plants that are growing there. It doesn't hold moisture like clay does, it allows it to pass through slowly. It both holds it and allows it to drain.” –SB

For now, the matter is up for debate. It will not be included in the Healthy Soils Program until enough people ask for it during a public comment period and then they would need to collect enough data on it through Demonstrations before it could become eligible through the Incentives Program. But that won't stop Stuart from doing a few small experiments here and there as he can swing them. 

“I don't want to say ‘Oh, I'm not going to play in your sandbox, cause you're not playing the right game.' I'm going to play in the sand box, and at some point I will introduce the right approach, and maybe somebody will say ‘wow that really works.' … I want to participate AND I want to do the right thing.” –SB 

Alder Springs Vineyard- November 2019

 

To learn more about Stuart and Alder Springs Vineyard, you can find their website online at https://www.alderspringsvineyard.com/ and follow them on Instagram @alderspringsvineyard.

To learn more about the work of the North Coast Soil Health Hub, particularly their soil health assessments for Northcoast vineyards, their website is http://soilhub.org/.

Climate smart agriculture encompasses management practices that increase soil carbon sequestration, reduce greenhouse gas emissions, improve yields and efficiencies, and promotes climate resilience. The California Department of Food and Agriculture (CDFA) supports three funding opportunities in climate smart agriculture: the Healthy Soils Program, the State Water Efficiency & Enhancement Program, and the Alternative Manure Management Program.

In a collaborative partnership, CDFA and UC Agriculture and Natural Resources have teamed up to support 10 Community Education Specialists throughout the state to provide technical assistance and outreach for the climate smart agriculture programs. To learn more and locate a specialist near you, visit http://ciwr.ucanr.edu/Programs/ClimateSmartAg/.

 

There has been much buzz and renewed interest recently in planting trees as a tool to combat both the causes and impacts of climate change. But what role do trees play in climate-smart agriculture?

With respect to building healthy soils, tree canopy and leaf litter can provide protection against wind erosion and temperature extremes. Tree roots can help stabilize soils, increase nutrient cycling, and improve soil biota representative of a healthy soil system. The incorporation of trees and shrubs on agricultural landscapes, known as agroforestry, blends the practices of forestry and agriculture and can provide many ecological and economic benefits.

Photo by Jet Kim on Unsplash

The USDA defines agroforestry as “the intentional combination of agriculture and forestry to create productive and sustainable land use practices” [1]. In theory, it really is this simple: adding trees or shrubs to an agricultural landscape. In practice, like most things in agriculture, it is more nuanced and, of course, site specific. Agroforestry includes a suite of practices with varying degrees of complexity that yield systems also of varying degrees of complexity. The most common agroforestry practices in the U.S. are: alley cropping, silvopasture, riparian buffers, windbreaks, and multi-story cropping (also referred to as forest farming). 

Like many of the practices that fall under the header of climate-smart agriculture, agroforestry is both old and new. While the term agroforestry is relatively new, agroforestry has been practiced for millennia, yielding diverse, multistoried food forests in both temperate and tropical climates. The recent interest in agroforestry of the last few decades has been driven in part by the desire to apply the benefits of perennial agriculture to address some of the challenges of row crop and animal agricultural systems. 

When considering transitioning to agroforestry practices, it is crucial to understand in advance how the incorporation of perennial woody plants will impact your existing operation. Select trees and shrubs that will grow well in your climate and the specific conditions of your farm, and will complement - not compete with! - existing crops or pasture. 

Windbreaks Photo by Adrien Olichon on Unsplash

In addition to plant selection, site design and management are also key. For example, where you plant trees or shrubs on your farm in relation to other crops or other elements of your farm can determine whether there is synergy or competition for water and nutrients. Site design can also determine the need for different types of management, such as in alley cropping systems where the widths of the “alleys” between rows of trees must factor in the size of any machinery used.

A local example of agroforestry in action is at King & King Ranchin Fillmore. The King family received a Healthy Soils Program Incentive Grantaward to establish a windbreak along a 32-acre plot that is transitioning out of vegetable cultivation. The windbreak will protect the soil from the intense Santa Ana winds that sweep through the valley, establish living roots, sequester carbon in the woody biomass of the trees, and provide habitat for local pollinator and bird populations.

Photo of King & King Ranch Credit Gemina Garland-Lewis.

We will be highlighting more about agroforestry practices and the efforts of local producers in future blogposts, so stay tuned!

[1] USDA National Agroforestry Center. Agroforestry Practices. 2019. Available online: https://www.fs.usda.gov/nac/practices/index.shtml (accessed on 31 August 2018).