March 23, 2007 | General

San Diego County Targets Agriculture For Sustainable Organic Resource Management

BioCycle March 2007, Vol. 48, No. 3, p. 42
West Coast Conference Preview
Analysis of population dynamics verifies need to return compost and mulch to region’s farms to improve crop yields and reduce applications of water, fertilizer and pesticides.
Rich Flammer and Wayne Williams

SAN DIEGO COUNTY is number one in the United States for value of floricultural, nursery, greenhouse and sod products; number one in the nation in small (under 10 acres) farms; and third in the state of California in total agricultural production. The farmlands in southern California have the potential to play a major role in organic resource processing and finished use.
The agricultural industry is a vibrant component of the economy of San Diego County and increased in both worth and acreage in 2005. Total reported value for all agricultural commodities produced in the county during the same year was over $1.5 billion, the highest crop value ever reported for the county. Further, 2005 was the 13th consecutive year of growth in value for agriculture, as acreage dedicated to farming increased by three percent. Indoor flowers and foliage plants were the number one crop with a value of over $311 million. Hass avocado acreage increased by three percent, with production increasing by 33 percent.
While San Diego County has the sixth highest urban population among counties in the United States, it remains unique in that it’s the 12th largest agricultural economy. The region owes its botanical bounty to both its geography and geology, with mild Pacific Ocean temperatures eliminating most frosts along the coastal corridor, and a multitude of valleys, foothills, and major slopes stretching from the ocean to the eastern Palomar and Laguna ranges rising to elevations of 6,000 feet. The mountains act as a catchment for higher altitude rains, and buffer the coastal region from the harsh and hot desert lands to the east.
The influx of people into southern California and San Diego County increases daily. California’s population grew from 34.2 million in 2000 to more than 37 million in 2006, and the state’s Department of Finance predicts over 48 million by 2030. In 2006, San Diego County had 3,066,820 people, and another 850,000 are expected to arrive by 2030. Human migration to California over the past 50 years has been the greatest recorded movement of people in the history of the earth, not only expanding societal and environmental challenges, but bestowing enormous pressures on agricultural production.
Suburbs have crawled over native chaparral, destroying most of it. This horizontal sprawl has created a megalopolis in all of southern California, particularly along the coastline, from Santa Barbara in the north to San Ysidro on the Mexican border in the south. With nearly 250 miles of solid houses and cities, only a few short stretches of open space are left. And as the population explodes, the trend has been to build further and further east, into the valleys, driving out agriculture, and displacing it to mountain slopes, and more inaccessible districts. Hence, only a few agricultural fields and farms along the coastal zone, including the valleys, remain in San Diego County today.
Where extensive and productive fields of stake tomatoes, peppers, strawberries and basic food commodities once grew at the very edge or integrated with the county’s towns, now houses and condos rule supreme. As the County of San Diego urbanized, heirs of farms sold land for lucrative conversion to housing. But as an example of agriculture’s ability to evolve with the increase in population, avocados are now the leading fruit industry in the county, with 26,326 acres on mostly steep hillsides, and a production value of over $252 million in 2005. The avocado orchards account for most of the expansion.
With the influx of people to California came many of their favorite plants, a multitude of “eastern” species, especially trees and grasses to create “back home” style landscapes and manicured green lawns. In the deserts of San Diego County, with the exception of the small gallery forests along the few streams and rivers, and at higher altitudes in the mountains, there are no native trees.
Water was imported from the Colorado and Sacramento rivers up to 500 miles away and transformed the bustling and growing southern California cities. This precarious supply helped the region forget that the county remains a desert. Many plant species were introduced from the eastern United States and other Mediterranean climates, so olives, liquid ambers, tulip trees, weeping willows, maples, magnolias and especially eucalyptus and their many relatives, joined the mix. Along with these hundreds of introductions came many kinds of plants that escaped, to invade the chaparral and coastal sage, crowding out the native species and creating long-term problems in vegetation management.
While the mass of immigrant trees, bushes, herbs, forbs and grasses have created an enormous challenge, the landscaping industry in San Diego County has enjoyed becoming economically robust through keeping all this vegetation in check and looking nice according to the “back east” vision of how surroundings ought to appear. Xeriscaping and other native landscaping scenes are almost nonexistent, and despite some programs for water conservation, green lawns and nonendemic species prevail and consume moisture in gluttonous proportions, while struggling to grow in poorly structured, nutrient deficient soils. Native species have adapted to these marginal desert conditions. Most nonnatives have not.
To compensate for the soil deficiencies and health challenges that the nonendemic plants experience, loads of synthetic fertilizers and pesticides are applied. Unfortunately, the predominate sands and clay in the region lack the physical structure and chemical make-up (i.e. cation exchange capacity) to bind nutrients, and much of what’s applied ends up in local streams and creeks, and eventually the Pacific Ocean.
With so many people and so much artificially planted vegetation, an enormous amount of biomass produced in San Diego County has to be dealt with. Everyone who has plants in their landscaping, including the agricultural sector, somehow has to manage the residuals from pruning, cutting, harvesting and the like. In agriculture, traditional methods for organics management entailed plowing in the stubble, chipping and grinding the prunings and composting them, or spreading them as “green manure” on fields and orchards. Animal manures were cast directly on the fields and turned under, or composted with a mixture of chipped and ground green matter. In cities, the traditional vegetative management practice is to water as much as possible, cut the lawn too frequently, fertilize the plants to the point of leaf burn, and prune everything in excess, finally placing the material at the curbside for trash haulers to cart it away for burial in local landfills.
Currently, a large portion of San Diego County’s organics are being buried or used at the landfill for “alternate daily cover,” or “ADC,” a material created by grinding curbside collected (and to a lesser degree, commercially generated) landscape trimmings and dimensional lumber and used to cover garbage at the end of each day of landfilling. Other materials can also be used as ADC, including auto fluff, soil, foam, and tarps. While ADC is not considered disposal by the California Integrated Waste Board (CIWMB), it still takes up significant landfill space. San Diego County as a region is presently landfilling between 15 percent and 27 percent of its total solid waste in the form of green and other compostable organic materials. There is a multitude of economic and environmental detriments associated with long-term use of landfilled organic material and ADC.
ADC as included in a diversion inventory is unique to California, and controversial. SB 1778, introduced on February 24, 2006 by State Senator Richard Alarc&oagrave;n, would have required “…that if the alternative daily cover is comprised of woody and green material, as the bill would define that term, that material (is) not to be considered as being diverted and (is) to be included in the amount of solid waste that is subject to disposal for purposes of the diversion requirements of the (California Integrated Waste Management) act…” Although this bill failed to pass, this is the fourth of its kind to be introduced in the past six years, testifying to a growing concern against the use of landscape and clean construction organics for use as alternate daily cover in landfills.
ADC use has seen a marked increase since 2001, impacting the viability of the region’s composting industry and eliminating the potential for hundreds of thousands of tons of nitrogen and other essential plant nutrients to be recycled back into endemic soils already marginal in the physical and chemical composition necessary to sustain healthy plant growth.
In 2006, the California Integrated Waste Management Board announced that California had reached 50 percent diversion during 2005. Although numerous jurisdictions had not complied, all cities had made significant efforts toward reaching that goal. The jurisdictions of San Diego County are obligated to maintain the 50 percent diversion rate, and periodically assess their programs of compliance. Falling below the requirement can result in fines and penalties of up to $10,000 per day. Most of the jurisdictions in San Diego County are now in compliance, but the demographics and the booming Southern California economy are interfering with maintenance of the required mandate, and the CIWMB is currently contemplating a higher diversion rate, following the examples of San Francisco, Los Angeles, San Jose and Oakland, who have either declared a goal of 75 percent diversion in the next few years, or “Zero Waste” as an option.
Further, Governor Schwarzenegger has declared that by 2020, 20 percent of the electricity production in California will be gleaned from biomass plants. Thus a new stage is set to reduce landfilling, use biomass in better ways, and prolong existing landfill space for the future.
As the inventory of compost facilities in the region declines, the more than 6,000 farms in San Diego County represent a logical processing option for organics generated and disposed of in this region. With existing resources such as fallow, but available land, farm machinery that could double as composting equipment, excellent composting feedstocks generated on-site, and built-in markets (i.e. the potential to use finished products in a farm’s own growing operation), the agricultural sector possesses vast possibilities for helping the region with the most beneficial processing options for both commercially-generated and curbside-collected organics.
The benefits of this material to the farmer – whether composted, mulched, or directly land-applied – are numerous, and include improvement in crop yields and decreased use of water, fertilizer and pesticides. Environmental benefits range from decreased erosion and less contamination of local water sources, to minimized health risks to farm workers. From an economic perspective, agricultural businesses stand to gain from diversified operations and the additional revenue stream composting represents, as well as opening the opportunity to supply produce for the rapidly growing, multibillion dollar organic food industry. On-farm organics processing offers regional benefits of new job creation, sustainable farming practices, and preservation of natural resources.
In the fall of 2003, a fire burned 392,000 acres in San Diego County – including most of the pine and fir forests of the Laguna Mountains. Over 5,600 buildings and nearly 4,000 vehicles were destroyed, and 16 people died.
The Federal Emergency Management Agency (FEMA), the U.S. Forest Service and the National Resource Conservation Service (NRCS) provided federal funds to help the County of San Diego with the clean-up. A smaller, but equally as serious fire also occurred at about the same time in San Bernardino, east of Los Angeles. Much of the remaining burned, dead and dying trees and chaparral from the San Bernardino fire were disposed of in open flame curtain ovens, or landfilled. Wood residues were also transported to the Colmac energy plant on the Cabazon Indian Reservation in Mecca.
Since the San Bernardino disaster and clean-up occurred just before the San Diego fire, it was feared that selling more wood to Mecca would depress the wood fuel market, and harm local recycling businesses. The county had just finished its update of determining available landfill space, and a massive increase in material from the fire would have shortened the life of local landfills. Hence, special contingency programs were implemented. The County of San Diego required that all contractors be prohibited from landfilling any biomass from the fires.
The county created forest treatment criteria. In the process of assuring human safety, the first criterion was to protect the forest and chaparral ecosystems. Slash, stems, and other small vegetative debris in the corridors were chipped and spread on the ground in the immediate areas, including all road and trails used by harvesting equipment. This amounted to about one-third of the biomass. The chips and mulches protected the soil from erosion, but were not applied deeper than five inches to permit the light to penetrate and facilitate seed germination and resprouting of fire-adapted species.
As felled trees hit the ground, they became the property of the contractors, who transported the marketable saw logs to various mills… as far away as Washington State, with one load even going to China. Three local sawmills and several Alaska mill sites were opened as well. Any remaining chips were transported and sold to Colmac. Chips were also transported to local landscaping companies and composters as far north as the Los Angeles basin.
With the U.S. Forest Service biomass utilization grant, the County of San Diego developed new markets for wood chips. Agriculture became a major target, especially the valuable orchards in the county. Apple orchards at higher elevations applied approximately 15,000 tons of chips. Citrus and avocado orchards in the nearby foothills and valleys accepted another 15,000 tons, and about 15,000 tons of chips and slash were transported to various landscaping companies in San Diego, Orange and Riverside counties for mulching and composting.
A preliminary economic model of the program determined that 176,466 merchantable trees were harvested, mainly of incense cedar, ponderosa and Jeffrey pine, white fir, and Coulter pine. Live and black oaks were sawn into firewood, much of which was supplied free to residents. Approximately 447,300 board feet of lumber was produced, and about 1,427,000 board feet of chips and firewood. This resource provided about $15 million to the economy. After grant costs and a conservative 2.5 economic multiplier, there was an estimated net gain to the economy of nearly 11 million dollars.
During the salvage logging operations, several workshops were held at the Tierra Miguel Foundation’s organic farm to bring stakeholders together to discuss how to open agricultural sector markets, answer farmers’ questions about costs and risks, determine what equipment and financing would be necessary, and proceed with research and demonstrations that would bring the biomass to the farm. This Forest to Farm Program emphasized that chips applied to orchards would significantly reduce irrigation water needs, improve soil tilth and nutrition, and reduce several severe root diseases. Currently there are about 100 farms signed up for chips. The Tierra Miguel workshops served as a gristmill for marketing strategy development.
Concurrent with the Tierra Miguel workshops, the county also addressed regional issues related to increasing the composting infrastructure, lack of end-product market focus, and improvement of land use rules to facilitate sound organic resource management.
Through research and discussions with industry representatives, it became clear that several other large and essentially insatiable markets were available, but underdeveloped. The lion’s share of compost and mulches sold at the retail level is actually imported from out of county. With forecasted increases in the number of housing units countywide at about 10,000 per year (San Diego Association of Governments, or SANDAG), a major need for composts and mulches in CalTrans (a state agency responsible for highway, bridge, and rail transportation planning, construction, and maintenance) highway projects, and agriculture’s 273,000 acres potentially available for biomass utilization, it was discovered that a large enough local market existed for using all 1.2 million tons of currently landfilled biomass in San Diego County.
To initiate such an ambitious plan, the Solid Waste Planning and Recycling Section of the Department of Public Works of San Diego County held a series of workshops to formulate a County Organic Resource Management Policy. The San Diego County Integrated Waste Management Plan, a countywide multijurisdictional program, states: “The Cities and County shall strive to strengthen markets for reusable, recyclable, and compostable materials by instituting policies and programs to ‘buy recycled’ content products.” The county’s efforts coincide with the goals and spirit of the plan.
Under the direction of the county, and in cooperation with the Integrated Waste Management Local Task Force, Citizens Advisory Committee, the County Organic Resource Management Project brought stakeholders together to ensure a common understanding of the issues and open a dialogue to frame a long-term sustainable organic resource management strategy. A total of six meetings were held with a wide variety of stakeholders, including composters, county planners, city representatives, solid waste/ recycling collectors, and those who purchase, sell or use organic soil amendments commercially.
Stakeholders identified barriers to highest and best organic resource processing and market development. These barriers included: the need to update local land use policies and zoning ordinances, insufficient number of organic management facilities, landfill use of organic materials as alternate daily cover, economic disincentives to recycle, and the strategically sparse marketing efforts for finished products. Stakeholders then developed a collective vision for increasing the highest and best use of organic resources, promoting sustainable markets through such practices as increased organic agriculture, and utilizing the benefits of organic products to preserve watersheds, increase soil fertility, and reduce toxin levels in the regional environment.
A regional conference was held, and the committee decided the following key components were necessary to achieve better organic resource management in San Diego County:
o Modify land use and zoning ordinances to facilitate composting;
o Formulate and implement an increased strategic investment in sustainable organics resource management and finished product marketing;
o Develop a system of information exchange, training, and standards for the industry and relevant public sector interests, and
o Form an advisory board to guide the process.
Having identified regional issues, and to follow through on “increased strategic investment in sustainable organics resource management and finished product marketing,” the county hired Richard Anthony Associates (RAA), which worked closely with the San Diego County Farm Bureau, to identify local farmers with an interest in exploring the establishment or expansion of on-farm composting operations, direct land application, and utilization of soil amendments and mulches.
Responses were received from various agricultural sectors, including dairy, poultry, containerized and row crops, and a commercial developer with land suitable for crop establishment. Five operations were chosen, and case studies were done to assess the viability of establishing, or increasing on-farm organic resource management.
Through assessment of the findings gathered in the study, it was determined that farms and ranches represent a huge, untapped resource for managing organics in the region, but require assistance in permitting, design, and management of composting operations, as well as help with funding, equipment selection, and finished product utilization and market development. Farms studied were in various regions of the county. For a successful, sustainable, and cost-effective organic resource management program, strategically positioned locations were imperative for establishment of on-farm composting projects.
San Diego County is a unique region, having several climatic zones, a diverse, growing population, rich agricultural heritage, and a farming industry that produces fruits, vegetables, flowers, trees and shrubs for the entire United States and a multitude of countries throughout the world. Through proper resource management, the county’s quality of life can be preserved, and even improved.
While direct land application and on-farm composting are proven methods successfully utilized throughout the United States for efficient resource management and sustainable agriculture, the San Diego County farming community has yet to fully exploit the potential of these methods. Given the current challenges of the county with regard to resource management, erosion, water pollution, overdevelopment, and air quality, the region stands much to benefit from transitioning away from burying organics in the landfill – whether outright or through alternate daily cover – and returning them to the farm. The County of San Diego and committed stakeholders intend to pave the road required to make this happen.
Rich Flammer is owner of Hidden Resources, a composting consulting firm. He can be reached at Wayne Williams, Ph.D., is Program Coordinator for Solid Waste Planning and Recycling, County of San Diego Department of Public Works. He can be contacted at The opinions expressed in this article are solely those of the authors, and do not necessarily reflect the views and policies of the County of San Diego.
AS of 2005, the county landfilled 4.2 million tons of solid waste with compostable organics representing between 630,000 and 1,134,000 tons. Such an amount of landfilled biomass poses significant environmental impacts, being the potential source of substantial volumes of leachate and greenhouse gases. The county’s landfills are currently emitting some 53 million cubic feet of methane per day. Some of this is captured for electricity production, but most is flared off, and an additional substantial but unknown amount of methane simply escapes through the liners into the atmosphere. Numerous reports emphasize that without organics in the landfill, these problems would essentially cease as the landfills returned to their intended “dry tomb” status, and the landfill-diverted organic material could be converted into economic assets. To increase diversion and reduce or eliminate landfill gas and leachate problems, 24 U.S. states have some type of yard waste ban in place.
THE 23rd Annual BioCycle West Coast Conference – to be held April 16, 17, 18, 2007 in San Diego – will feature sessions by Wayne Williams (coauthor of this report) and Ric Anthony on “Moving A County Toward Zero Waste Goals.” It will cover how San Diego County – ranked sixth largest urban population and 12th largest agricultural economy in the U.S. – is ideal for managing organic residuals on farms. Steps on this journey include modifying land use and zoning ordinances, while increasing applications of green residuals for improved crops and soil quality.
Other topics featured will focus on how organics recyclers and composters are advancing renewable resource management and profitability goals, and providing lessons in selling compost-based soils, mulches and fertilizers.
For registration details and complete Conference agenda, see pages 15-17 in this issue.

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