SAN JOAQUIN VALLEY AIR POLLUTION CONTROL DISTRICT

1 2015 Agricultural Burn Report 

Final 2015 Agricultural Burning Review

December 2015

1 Executive Summary 

Historically, the practice for disposing of agricultural materials has been through the 

open burning of the materials in the field. Burning agricultural materials provided an

economically feasible method for the timely disposal of these materials, helped prevent 

the spread of plant diseases, and controlled weeds and pests. Addressing the air

quality impact from open burning has been a priority, and the District, ARB and Valley 

farmers have implemented a number of measures to minimize that impact over the 

years.

In 2003, California Senate Bill (SB) 705 (California Health and Safety Code Section

(H&SC) 41855.5 and 41855.6) established a schedule for specific types of agricultural

material to no longer be openly burned in the field, but provided for a postponement of

the phase-out where justified by technical and economic impediments. The San

Joaquin Valley Air District (District) has implemented SB 705 through Rule 4103 (Open

Burning) and the District’s smoke management program and have reduced the total

acreage of agricultural materials burned in the Valley by 80%. 

In 2010, the District prepared the 2010 Final Staff Report and Recommendations on 

Agricultural Burning1(2010 Report) which evaluated each crop category identified in 

H&SC Section 41855.5 and provided recommendations for allowing or prohibiting the 

open burning of categories as outlined by the senate bill. Based upon the 2010 Report, 

the California Air Resources Board (ARB) provided a two year concurrence on the 

District’s recommended postponements, based on the lack of feasible alternatives to 

open burning.

In 2012, the District prepared the 2012 Update: Recommendations on Agricultural 

Burning (2012 Report) which re-evaluated the technological and economical 

impediments for the crop categories that had been postponed. Based upon the 2012 

Report, the California Air Resources Board (ARB) provided an additional three year 

concurrence on the District’s recommended postponements, based on the continued 

lack of feasible alternatives to open burning.

This 2015 Agricultural Burning Review (2015 Review) shows that in the three years 

since the 2012 evaluation, the availability of technologically achievable and 

economically feasible alternatives to agricultural burning has significantly worsened due 

to the severe drought conditions and the demise of the biomass industry that historically 

has provided an alternative to open burning for a considerable amount of the 

agricultural waste generated in the Valley. This situation will likely get worse since there 

 

1

SJVAPCD. 2010 Final Staff Report and Recommendations on Agricultural Burning. 2010.
San Joaquin Valley Unified Air Pollution Control District December 14, 2015

2 2015 Agricultural Burning Review

are no federal or state funding commitments for the continued operation of biomass 

facilities.

Currently the District is facing numerous requests from growers to burn agricultural 

materials due to the decreasing demand for chipped agricultural waste by the biomass 

industry. If the biomass industry does not return to previous levels, this situation will 

only worsen, especially given the hundreds of thousands of acres of orchards, 

vineyards and other agricultural crops that have been fallowed in response to the 

drought or have been switched out due to crop change out. 

The District, therefore, requests continued ARB concurrence for the postponement of 

the remaining crop categories through 2020. The District will continue to evaluate these 

categories on an ongoing basis and as required under Rule 4103. If the long-term 

viability of the Valley’s biomass power plants continue to decline and feasible 

alternatives to open burning are not found, consistent with the provisions specified in 

California Health and Safety Code, the District may be forced to re-evaluate the open 

burn prohibitions currently in place. 

The District will continue to carefully manage all remaining agricultural burning with its 

Smoke Management System (SMS) to ensure that there is no violation of the National 

Ambient Air Quality Standards. The District will also work closely with farm bureaus, 

County Ag Commissioners and agricultural representatives to explore and advance 

agricultural wood waste disposal techniques as alternatives to open burning and 

traditional biomass power plants.

2 Regulatory Background

2.1 Senate Bill 705

In 2003, Senate Bill 705 amended state law to require the District to limit open burning 

of agricultural material in accordance with a phased-in schedule of deadlines. In 

addition to those requirements, the state law directs the District to postpone the burn 

prohibition dates for specific types of agricultural material if the District makes three 

specific determinations and the Air Resources Board (ARB) concurs. 

(1) There are no economically feasible alternatives to open-burning of the 

specific type of material; 

(2) Open-burning the specific type of material will not cause or substantially 

contribute to a violation of a National Ambient Air Quality Standard (NAAQS); 

and 

(3) There is no long-term federal or state funding commitment for the continued 

operation of biomass facilities in the Valley or the development of alternatives to 

burning. 
San Joaquin Valley Unified Air Pollution Control District December 14, 2015

3 2015 Agricultural Burning Review

SB 705 prohibits the issuance of a burn permit for specific categories of agricultural 

material and requires the District to regulate the burning of diseased crops and establish 

best management practices (BMP) for the maintenance and control of other weeds. 

The following table shows the requirements for specific categories of agricultural 

material and their corresponding prohibition dates.

Table 1 Timeline for SB705-Specific Crop Category Requirements

Effective Date Category of Agricultural Material

June 1, 2005

Prohibit burning for Field Crops, Prunings, and Weed Abatement 

Establish BMP for Other Weeds and Maintenance 

Regulate burning of diseased crops 

June 1, 2007 Prohibit burning for Orchard Removals 

June 1, 2010 Prohibit burning for Vineyard Removals, Prunings from Surface Harvested 

Crops and Other Materials

2.2 District Rule 4103 (Open Burning) 

District Rule 4103 (Open Burning) was first adopted on June 18, 1992 to permit, 

regulate, and coordinate the use of open burning while minimizing smoke impacts on 

the public. Rule 4103 has subsequently been amended numerous times to incorporate 

state law requirements. The provisions of Rule 4103 apply to open burning conducted 

in the Valley; this rule is not applicable to prescribed and hazard reduction burning, as 

defined and regulated by District Rule 4106 (Prescribed Burning and Hazard Reduction 

Burning). 

Rule 4103 was last amended in April 2010 to incorporate the provisions of Senate Bill 

705 (CH&SC §41855.5 and §41855.6) directly into the rule to more efficiently allow the 

District to consider the feasibility of non-burning alternatives for specific crops and 

materials, and postpone the burn prohibition. 

Rule 4103 contains requirements for collecting, sorting, drying, and igniting agricultural 

materials; the timing, monitoring, and maintenance of burns; and specific requirements 

for field crop burning, ditch bank and levee maintenance, contraband materials, Russian 

thistle (tumbleweeds), and diseased materials. Additionally, the rule details a set of 

conditions that must be met for a burn permit to be issued.

The rule provides for the APCO to restrict and allocate burning based on meteorology 

and the predicted smoke production. Rule 4103 prohibits issuing permits for the 

burning of field crops, prunings, weed abatements, orchard removals, vineyard removal 

materials, surface harvest prunings, and other materials described in the rule.
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4 2015 Agricultural Burning Review

2.3 The District’s Smoke Management System 

In 2004, the District established the Smoke Management System (SMS), a refined 

method of authorizing or prohibiting individual open burns based on modeling the air 

quality impacts of smoke. The entity requesting a burn permit must first provide the 

District with the acres and type of burn material, the specific location of the burn, and 

the date of the burn. This information is entered into the SMS, where acres are 

converted to tons of fuel burned using a fuel loading factor based on the specific crop to 

be burned. Emissions are calculated by multiplying the tons of fuel burned by a cropspecific emission factor.

2 A burn request will be authorized after analysis and review 

from the compliance staff, and only if sufficient emissions have been allocated to the 

burn zone. 

The proper management of burning allocations under the SMS ensures that open 

burning of agricultural materials does not cause any violations of health-based 

ambient air quality standards, open burning has only been permitted under the 

District’s comprehensive Smoke Management System (SMS), which uses real-time 

meteorological information to analyze the impact of burning on air quality and 

appropriately limit burn allocations by area. Under the District's SMS program, the 

Valley is divided into 103 zones, depicted in Figure 1. The amount of burning allowed 

in a given zone on a specific day is based on factors such as the local meteorology, 

the air quality conditions, the atmospheric holding capacity, the amount of burning 

already approved or happening in a given area, and the potential impacts on 

downwind populations. In order to avoid violations of relevant NAAQS, District staff 

must reduce and balance the impacts of agricultural burning, wildfires, and prescribed 

burning. In some cases when the wildfire smoke impacts are severe, no agricultural 

burning is allowed. In the summer of 2015 when wildfire smoke impacted the Valley’s 

air quality, the agricultural community had to be flexible to wait for the next burn 

window to appear. During this period, District staff worked hard to find burn windows 

under good to marginal dispersion conditions to allow agricultural burning to continue 

in the middle of the wildfire season.

 

2

ARB. District Miscellaneous Process Methodologies – Managed Burning and Disposal. Retrieved on 11/19/14 from 

http://www.arb.ca.gov/ei/areasrc/distmiscprocwstburndis.htm
San Joaquin Valley Unified Air Pollution Control District December 14, 2015

5 2015 Agricultural Burning Review

Figure 1. 103 Burn Allocation Zones in the Valley

3 Valley’s Success in Achieving Major Reductions in Open Burning

District staff has worked closely with stakeholders over the years to identify 

economically feasible alternatives to open burning of various agricultural materials and 

to meet its legal obligation under state law. These efforts have resulted in more than an 

80% reduction in agricultural burning. Figure 2 below shows the reductions in 

agricultural material burned since 2002. 
San Joaquin Valley Unified Air Pollution Control District December 14, 2015

6 2015 Agricultural Burning Review

Figure 2. Annual Average Agricultural Open Burning (Tons of Material Burned)

4 Burn Prohibition Date Postponements

4.1 2010 Final Staff Report and Recommendations on Agricultural Burning 

In the 2010 Report, the District evaluated each crop category identified in CH&SC 

§41855.5 to determine any technologically and economically feasible alternatives to 

open burning. After working extensively with stakeholders to understand viable 

alternatives and associated costs, the District provided recommendations for allowing or 

prohibiting the open burning of agricultural material categories. 

In the 2010 Report, the District made a determination, consistent with CH&SC 

requirements, to postpone the burn prohibition dates and allow continued burning of 

certain crop categories. The District determined the following for the crop categories 

specified in the third column of Table 2 below: 

 The continued conditional issuance of burn permits under the District’s SMS 

would not cause or substantially contribute to a violation of an applicable federal 

ambient air quality standard. 

 There were no economically feasible alternatives for these crop categories. 

 There were no long-term funding commitments for the continued operation of 

biomass facilities in the Valley in place.

0

200,000

400,000

600,000

800,000

1,000,000

1,200,000

2002 - 2004 2012 - 2014

Tons Burned (Tons/Year)

Weed

Abatement

Waste

Burning

Field Crops

Vineyards

Orchard

Removals

Attrition

Prunings
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7 2015 Agricultural Burning Review

Table 2 Crop Category Prohibitions 

Crop 

Category

Specific Crop Types

Burn Permits Prohibited Burn Permits Allowed

Field 

Crops

Alfalfa, asparagus, barley stubble, 

beans, corn, cotton, flower straw, hay, 

lemon grass, oat stubble, pea vines, 

peanuts, safflower, sugar cane, 

vegetable crops, and wheat stubble 

Rice stubble up to 70% of the total 

acreage of rice farmed by the operator 

per year

Residual rice stubble, spot burning of 

rice stubble, and burning of weeds and 

vegetative materials on rice field levees 

and banks

Prunings

Apricot crops, avocado crops, 

bushberry crops, cherry crops, 

Christmas trees, citrus crops, date 

crops, eucalyptus crops, kiwi crops, 

nectarine crops, nursery prunings, olive 

crops, pasture or corral trees, peach 

crops, persimmon crops, pistachio 

crops, plum crops, pluot crops, 

pomegranate crops, prune crops, rose 

crops, and fig crops

Apple crops, pear crops, and quince 

crops

Weed 

Abatement

Berms, fence rows, pasture, grass, and 

bermuda grass

Weed abatement activities affecting 

ponding and levee banks

Orchard 

Removals

Orchard removal matter of more than 

15 acres at a single location, per 

calendar year, citrus crops > 3,500 

acres

Citrus crops < 3,500 acres, apple crops, 

pear crops, quince crops, and orchard 

removal matter from a total of 15 acres 

or less of orchard removal at a single 

location, per calendar year

Vineyard 

Removals None at this time Vineyard removal materials from grape and kiwi crops

Surface 

Harvested 

Prunings

Grape canes (defined as "vineyard 

materials"), grape vines, and prunings 

of almond, walnut, and pecan crops for 

each agricultural operation whose total 

nut acreage at all agricultural operation 

sites is 3,500 acres or more

Raisin trays (defined as "vineyard 

materials"), and up to 20 acres of 

prunings per year for almond, walnut, 

and pecan crops for agricultural 

operations whose total nut acreage at 

all agricultural operation sites is less 

than 3,500 acres with a case-by-case 

allowance of additional burn requests 

based on economic feasibility

Other 

Materials Brooder paper and deceased goats Diseased beehives

On May 27, 2010, ARB provided a two-year concurrence with the District’s extension of 

the burning prohibition date for specific crop categories3. ARB’s evaluation concurred 

that there continues to be a number of impediments to fully implementing alternatives to 

burning for selected crop categories. 

 

3

CARB. (2010). Resolution 10-24. Retrieved 9/21/15 from http://www.arb.ca.gov/smp/district/finalres1024.pdf. 
San Joaquin Valley Unified Air Pollution Control District December 14, 2015

8 2015 Agricultural Burning Review

4.2 2012 Review of 2010 Report4 

In compliance with ARB’s two-year concurrence, the District revisited the 2010 Report in 

2012. The 2012 review of the 2010 Report determined there were no significant 

changes in the economic feasibility of alternatives to agricultural burning since 2010 and 

therefore concurred with the results of the 2010 Report. On May 31, 2012, ARB issued 

a letter to the District explaining its concurrence with the 2012 review and approved an 

additional three years for the postponement of the remaining crop categories.5

5 Effects of the Drought on Agricultural Burning 

California is currently suffering through the worst drought in recorded history. Despite 

improved atmospheric conditions during the winter of 2014-2015, precipitation remained 

well below average for most of the Valley. Snow pack levels during winter of 2014-2015 

hit a record low at 6% of normal. Since January 2014, the Governor declared California 

to be in a state of Drought Emergency, and the entire Valley is under “exceptional” 

drought conditions. Federal and state surface water deliveries are at an all-time low of 

zero- to twenty-percent allocation, and cities and towns have implemented a mandatory 

25% reduction in water usage.

The drought conditions described above have resulted in a significant increase in 

fallowed land, with far more expected to follow. To date hundreds of thousands of acres 

of orchards, vineyards and other agricultural crops have been fallowed in the San 

Joaquin Valley in response to the drought. Removal of agricultural material has 

increased significantly and is expected to continue increasing for several more years. 

With the biomass industry in jeopardy, the extra agricultural material has nowhere to go. 

 

4

SJVAPCD. 2012 Update: Recommendations on Agricultural Burning. 2012

5

Air Resources Board. (2012, May 31). 2012 Ag Burn Concurrence Letter May 16.
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6 Current Economic Feasibility of Alternatives to Open Burning

6.1 Biomass Power Plants in Jeopardy

Biomass power plants are a significant alternative to the open burning of agricultural 

waste and the emissions associated with it. Biomass burning of agricultural material is 

preferable to open burning as it combusts the material more completely, results in fewer 

emissions, and provides an alternative source of energy in the Valley. 

6.1.1 Challenges for Biomass Power Plants 

The biomass industry is primarily the product of the Public Utility Regulatory Policy Act 

(PURPA) which was enacted in 1978 at the height of the energy crisis to promote the 

use of alternative nonutility power generation. Today, these facilities are fully 

depreciated and have lost, or are nearing the ends of, their long-term contracts to sell 

their power to the utilities. In addition, biomass facilities are facing numerous obstacles 

to remain in operation including price disadvantage, demand for intermittent power 

instead of baseload power, and lack of federal and state funding.

Much has changed in the energy markets since PURPA was implemented. Natural gas 

has replaced oil for electricity generation, and supplies of natural gas have increased, 

driving down the wholesale cost of electricity. California has adopted a Renewable 

Portfolio Standard (RPS) that requires 33% of the power that is purchased by utilities be 

renewable. This has driven competition to fill the renewable energy needs of the state. 

Under the RPS, Investor Owned Utilities (IOUs) have tended to favor lower cost 

intermittent sources of renewable power, such as solar and wind. This has left the 

biomass industry in a position where the power that they produce is not desirable, since 

most biomass plants provide baseload power instead of intermittent power, and the 

current rate being paid for power does not allow them to remain viable.

Given the current energy policy, the biomass industry does not compete well under the 

current procurement policies of the state’s IOUs. Historically, the biomass facilities 

have demanded 12-13 cents per kilowatt-hour, which has been necessary to retain 

economic viability. Pricewise, this places biomass facilities at a competitive 

disadvantage with other renewable fuels that can be procured at a much lower cost. 

Under the state’s RPS, program pricing information is confidential, however, anecdotal 

evidence is that currently the IOUs are purchasing power from solar and wind facilities 

at approximately 8 cents per kilowatt-hour.

Another factor that negatively impacts the competitive position of biomass generated 

power is due to the fact that such plants provide “baseload” power. As baseload 

generators, biomass facilities cannot produce power that can be turned on quickly, and 

therefore, cannot meet the power system’s demand for “ramping services”. The 

demand for ramping services is compounded by continued increase in the use of wind 

and solar renewable sources, which is partially triggered by the state’s RPS goals. If 
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10 2015 Agricultural Burning Review

current trends persist, this issue will worsen in the future. It is estimated that by 2020, 

solar and wind will account for three-quarters of the state’s renewable power and 20% 

of the state’s total electricity supply. The net effect of this is a further transition away 

from baseload generators to more flexible generators that can be turned-on and turnedoff when needed. Under this scenario, not only do biomass facilities have difficulty 

competing directly on price, but they also do not provide the type of power that is 

desired. While under this scenario the state can meet its renewable power goals, the 

potential loss of biomass plants can impact the state’s broader greenhouse gas 

reduction goals under AB 32 by increasing GHG emissions in sectors that currently rely 

on biomass plants for disposal of materials including the agricultural industry, landfills, 

and forests.

The biomass industry also struggles to provide consistent service to farmers needing 

timely removal of material to ensure the land is ready for the next planting season. In 

the past, lack of coordination and available storage for biomass fuels has caused 

uncertainty over the timing of material removal. The inability to guarantee consistent 

acceptance of agricultural biomass offers further confirmation that remaining crop 

categories should be allowed to continue open burning. A complete prohibition of open 

burning would result in a massive increase in agricultural material requiring disposal, 

placing an even greater strain on an already precarious situation.

6.1.2 Effects of Biomass Power Plant Shutdowns

As shown in Table 3, since 2012, five Valley biomass facilities, have shut down 

operations. In addition, the Valley’s largest biomass plant (Covanta Delano) has 

stopped receiving new material as of November 1, 2015, and has informed the District 

that they plan to shut down operations at the end of the year because they have been 

unable to secure a viable Purchase Power Agreement. 

Table 3 Status of Biomass Facilities in the Valley

The loss of these facilities has considerably reduced the available options to dispose of 

agricultural wood waste, especially material from large orchard removals. As a result, 

many agricultural growers have lost the primary economically feasible disposal option 

for their orchard removal material. This could not come at a worse time as there has 

been an increase in the number of large orchard removals over the past year due in 

large part to the effects of the extreme drought emergency currently facing the state. 

Facility Name City Capacity (MW) Status

Rio Bravo Fresno Fresno 28.5

Covanta Mendota, LP Mendota 30.0 CLOSED Dec. 2015

Madera Power, LLC Madera 28.5 CLOSED Feb. 2012

Ampersand Chowchilla Biomass, LLC Chowchilla 12.5

Merced Power, LLC Merced 13.0

Thermal Energy Energy Dev Partnership, LP Tracy 20.5 CLOSED Oct. 2014

DTE Stockton, LLC Stockton 54.0

Covanta Delano, Inc. Delano 56.5 STOPPED RECEIVING Nov. 2015; CLOSING Dec. 2015

Sierra Power Corporation Terra Bella 9.4 CLOSED Jan. 2014

Mt. Poso Cogeneration Company, LLC Bakersfield 49.9

CRES Inc. d/b/a Dinuba Energy Dinuba 11.5 CLOSED Sep. 2015
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11 2015 Agricultural Burning Review

6.2 Availability of long-term federal or state funding commitments

The biomass industry has long relied on a combination of state and federal financial 

incentives to directly support their relatively higher production costs. These incentives 

have ranged from tax credits to monetary grants, but have all expired over the last 

decade. Examples of these programs include the federal Renewable Electricity 

Production Tax Credit, expired in 2013, state Existing Renewable Facilities Program, 

expired in 2011, and state Biomass-to-Energy incentive Grant Program, expired in 

2003. Therefore, there are currently no long-term federal or state funding commitments 

for the operation of biomass facilities or development of alternatives to burning.

6.3 Specific Crop Categories

6.3.1 Vineyard Removal Materials from Grape and Kiwi Crops

Grape and kiwi vine cultivation requires use of extensive trellis systems to support the 

vines. The support system consists of wires and may include wood or metal posts and 

stakes. In many instances, grape canes remaining after pruning get wrapped around 

the wires to provide the needed support. As vines mature and age, trellis wires become 

deeply embedded into the canes or cordons. To avoid mechanical damage to chippers 

and biomass power plants, the embedded wires need to be removed. Wire removal 

requires intensive manual labor, adding significant potential cost to vineyard growers. 

Many chipping operators refuse to process these materials because of the wires. In 

addition, due to the limited number of chipping contractors operating in the Valley, 

service may not be available according to the vineyard grower’s schedule, which can 

cause delays in planting for the following season. Furthermore, due to the deterioration

of the biomass industry, limited biomass plant capacity could prevent the acceptance of 

this material. Thus there is currently no economically feasible alternative to open 

burning of this material. 

Sending this material into landfills is not considered a viable alternative as landfills are 

required to divert wood and green materials. For these reasons, District staff concludes 

that there is no change to the determinations made in the 2012 assessment to continue 

to allow this category to be open burned through the District’s smoke management 

system. 

6.3.2 Citrus Crops Orchard Removal Matter less than 3,500 acres

Similar to vineyard removals, the chipping of citrus orchard removals with subsequent 

transport and processing at biomass power plants is considered the most 

technologically and viable alternative to open burning. As explained above, the 

biomass industry is in severe jeopardy and will have insufficient capacity to handle all of 

the orchard removal material generated in the Valley if open burning was completely 

prohibited for this category. Since conditions have worsened since the 2012

assessment, this category will continue to be allowed to be open burned through the 

District’s smoke management system and are evaluated on a case-by-case basis.
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12 2015 Agricultural Burning Review

6.3.3 Surface Harvested Prunings from Almond, Walnut, and Pecan Crops

Nut trees are usually pruned after harvesting, either late or early in the year. In the

past, growers generally open burned nut prunings to dispose of the material. However,

many growers have found alternative ways to convert prunings into something useful,

such as soil amendment. Many nuts growers are currently shredding the prunings and

leaving the materials on the orchard floor. The ability to shred the materials varies

among growers of different size farms and regions, with commercial shredders

potentially being infeasible due to either excessive cost or unavailability. Additionally,

there are also concerns for this practice, including preventing the pruning material from

interfering with the harvesting of the crop and potential build-up of chipped material on

the ground. This situation can then cause the chipped material to be picked up during

harvest. Although tilling could be done to bury the chipped material to promote faster

decomposition, growers try to minimize the number of tractor passes in their orchards. 

Leaving chipped material on the ground has caused issues during harvesting; therefore,

many growers have mostly relied on removing the pruning material from the field and

open burning the pruning material. Due to harvesting and pruning practices, there is a

short window of opportunity to have these types of prunings chipped. Some growers

usually find it more conducive to their operations to gather the prunings and burn them.

The economic feasibility of using an alternative to open burning surface harvested 

prunings is evaluated for every burn permit application received. Since the 2012 

assessment, there have been 81 applications to obtain approval to burn. There were 29 

approved applications, meaning the price to implement an alternative was economically 

infeasible. Twelve applications were denied due to the cost of the alternative provided 

determined to be economically feasible. The remaining 40 applications were withdrawn 

due to a variety of reasons. 

Based on the case-by-case evaluations of specific grower’s permit requests, there has

not been a significant change in the number of chipping contractors available, and the

option of shredding is still economically infeasible for some growers. For these reasons, 

District staff concludes that there is no change to the determinations made in the 2012 

assessment to continue to allow this category to be open burned through the District’s 

smoke management system. 

6.3.4 Other categories

6.3.4.1 Pome Fruit

Pome fruits include apple, pear, and quince crops. The primary concern for pome fruits

is their susceptibility to fire blight, a bacterial disease that kills blossoms, shoots, limbs,

and potentially the entire tree. Chipping/grinding and composting create a potential

opportunity for transfer and infection of nearby orchards. Fire blight is prevalent in the

Valley and is a difficult disease to control. Burning of infected material is a preventive

measure used by growers to help ensure the disease does not spread. In light of the

disease issue, the District concludes that there is no feasible alternative to burning

pome fruit prunings or orchard removal matter at this time.
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13 2015 Agricultural Burning Review

6.3.4.2 Raisin Trays

Raisin trays are paper trays used to dry the grapes on the ground. These trays contain

polymer so that the moisture on the ground cannot be absorbed in the raisin tray. The

grapes remain on the raisin trays until they meet the appropriate moisture content. In

the past, growers used recycling firms to dispose of the trays. These recycling firms

shipped the trays to China for reuse. However, due to the lower value of the U.S. dollar, 

China cut off the import of raisin trays and this alternative is no longer broadly viable. 

Since the polymer does not degrade quickly, soil incorporation is not a feasible 

alternative to burning raisin trays. In addition, due to the polymer, biomass facilities will 

not accept raisin trays.

6.3.4.3 Rice Stubble

Rice is planted in the spring and harvested in the fall. Once the rice is harvested, the

rice straw remains in the field for disposition. Reducing the amount of post-harvest

straw residue in the rice fields is important to the successful production of the next crop. 

Burning has been the historical cultural practice for removing straw and residues for the

rice industry. Another potential alternative is soil incorporation, but this requires water 

to be delivered to the operations post-harvest season. Most rice growers in the Valley 

are in the northern region and, due to the annual distribution schedules designated by 

irrigation districts, water is not available to be delivered post-harvest as needed. Most 

rice growers in the Valley also do not have access to water wells for their rice fields. In 

addition, the extreme drought has exacerbated this situation. Therefore, rice growers in 

the Valley do not typically rely on soil incorporation as a feasible option to dispose of 

their rice straw.

In 2007, District staff believed that rice growers could sell the rice straw to baling 

operators who would then sell it to their customers such as dairies. Therefore, the 

District prohibited open burning for 30% of rice stubble per year. Selling rice straw to 

baling operators worked well when there was a market for the baled rice straw, but this 

has not consistently provided an economically feasible option for rice growers. Due to 

the fluctuation in market demand for rice stubble, which impacts growers ability to 

effectively remove the material, and issues with water allocation, District staff 

recommended that open burning of rice stubble be allowed to continue for burns at 70% 

per year of the total acreage of rice farmed by the operator after June 1, 2010 and until 

June 1, 2015. There has been no significant change to the economic feasibility of

baling as an alternative to burning. Therefore, the District will continue to allow this 

category to be open burned through the District’s smoke management system. 

.
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14 2015 Agricultural Burning Review

7 Potential technologies to Provide Alternatives to Agricultural Open 

Burning

The District has found no breakthroughs in technologically achievable and economically 

feasible alternatives to open burning and traditional biomass power plants. While every 

effort should be taken to save this existing resource, the District believes that there is an 

urgent need to investigate other alternatives for the disposal of agricultural waste 

material. The following are potential technologies that the District may pursue through 

the District’s Technology Advancement Program. Funding from the California Energy 

Commission, Department of Energy, and others will also be needed.

Pyrolysis – Gasification: Pyrolysis is a possible path to convert agricultural biomass to 

higher value products. Pyrolysis is the heating of an organic material, such as biomass, 

in the absence of oxygen. It is the first step of producing a flammable gas called 

synthetic gas (syngas). Burning syngas to produce power offers certain advantages 

over directly burning the biomass because the gas can be cleaned and filtered to 

remove problematic chemical compounds. Using syngas is also potentially more 

efficient than direct combustion of biomass because the gas can be combusted at 

higher temperatures. Syngas can also be used to produce methanol and hydrogen, or 

converted into a liquid fuel. This is a viable alternative for farm-scale or small-scale 

power production, with lower emissions than existing biomass combustion power plants. 

There are currently a few operational units in California, including two in the Valley.

Bio-char: Bio-char is a name for charcoal when it is used for particular purposes, 

especially as a soil amendment. Like charcoal, bio-char is created by pyrolysis of 

biomass. Bio-char can increase soil fertility and agricultural productivity. Bio-char can 

also be processed into activated carbon that can be used for the removal of specific 

compounds from gaseous and liquid streams.

Bio-oil: Bio-oil, sometimes also known as bio-crude or pyrolysis oil is a mixture of 

organic compounds that is distilled from the products of fast pyrolysis of biomass at 

about 500°C. Bio-oil can be used as fuel in boilers and also used in power generation 

equipment. Bio-oil also can be upgraded to renewable transportation fuels, as well. 

Bio-oil with high cellulosic materials such as orchard debris is not currently commercially 

viable.

High Solids Anaerobic Digestion: Anaerobic digestion is a viable process that can be 

used to convert woody biomass, agricultural wastes, and municipal solid wastes into 

methane gas. Anaerobic digesters that process large amounts of woody biomass will 

require the use of chemical treatment or enzymes to speed the breakdown of cellulose.

Composting Biomass: Composting is the process by which organic material is broken 

down aerobically by bacteria and other microorganisms to form a biologically stable 

organic substance suitable as a soil amendment and plant fertilizer. Organic waste 

decomposes naturally in the presence of water, warmth, and oxygen. Composting 
San Joaquin Valley Unified Air Pollution Control District December 14, 2015

15 2015 Agricultural Burning Review

accelerates the process by adding moisture and maintaining an elevated temperature. 

Biomass is one of the sources of organic material for composting operations, but woody 

biomass must be well mixed with high nitrogen concentration materials to be an 

effective compost component. 

Fiberboard: Biomass can be treated and processed to produce fiberboard that can be 

used in the manufacture of various products. Fiberboard is a type of engineered wood 

product that is made out of wood fibers that are bonded together with resin. Types of 

fiberboard include particleboard, medium-density fiberboard, and hardboard. 

Fiberboard is frequently used in many industries, such as furniture production, and is 

generally made with waste material from wood processing facilities. 

Biomass Used as Mulch/Land Application/Soil Incorporation: Chipped or shredded 

agricultural biomass materials can be used to produce wood mulch. Wood mulch can 

be a mixture of shredded wood, bark, and compost. Wood mulch can be used in 

landscape projects or for erosion control. The material is primarily used to reduce 

erosion by protecting bare soil from rainfall impacts, increasing water infiltration, and 

reducing runoff. A significant portion of pruned orchard material is currently shredded 

in-row and used as mulch in the orchard. The shredded material can be left on the 

ground or can be incorporated into the soil when the field is tilled. Over time, the 

material decomposes into the soil, which adds valuable organic material to the soil and 

can lead to better water infiltration and soil quality. 

Cellulosic Ethanol Production: Cellulosic ethanol is an advanced next-generation biofuel 

that can be made from agricultural wastes, wood chips, switch grass, corn stover, forest 

wastes, fast-growing trees, and other plant material. Currently, ethanol produced in the 

United States is most commonly produced from corn kernels. In the United States, corn 

ethanol is primarily used as an alternative or additive to gasoline. Advanced biofuels 

are those that do not rely on the starch in corn kernels. Production of large quantities of 

ethanol from woody biomass will likely require the use of chemical treatment or 

enzymes to speed the breakdown of the cellulose in the biomass. Currently, the 

production of cellulosic ethanol is still predominately in the demonstration phase of 

development.

8 Recommended Actions

This 2015 Agricultural Burning Review (2015 Review) shows that in the three years 

since the 2012 evaluation, the availability of technologically achievable and 

economically feasible alternatives to agricultural burning has significantly worsened due 

to the severe drought conditions and the demise of the biomass industry that historically 

has provided an alternative to open burning for a considerable amount of the 

agricultural waste generated in the Valley. This situation will likely get worse since there 

are no federal or state funding commitments for the continued operation of biomass 

facilities.
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16 2015 Agricultural Burning Review

The District, therefore, requests continued ARB concurrence for the postponement of 

the following crop categories through 2020. The District will continue to evaluate these 

categories on an ongoing basis and as required under Rule 4103. If the long-term 

viability of the Valley’s biomass power plants continue to decline and feasible 

alternatives to open burning are not found, consistent with the provisions specified in 

California Health and Safety Code, the District may be forced to re-evaluate the open 

burn prohibitions currently in place. 

The District will continue to carefully manage all remaining agricultural burning with its 

Smoke Management System (SMS) to ensure that there is no violation of the National 

Ambient Air Quality Standards. The District will also work closely with farm bureaus, 

County Ag Commissioners and agricultural representatives to explore and advance 

agricultural wood waste disposal techniques as alternatives to open burning and 

traditional biomass power plants.

Table 4 Postponement of Burn Prohibitions 

Crop 

Category

Specific Crop Types 

Allowed to Burn

Field 

Crops

Rice stubble up to 70% of the total acreage of rice farmed by the operator per year

Residual rice stubble, spot burning of rice stubble, and burning of weeds and 

vegetative materials on rice field levees and banks

Prunings Apple crops, pear crops, and quince crops

Weed 

Abatement Weed abatement activities affecting ponding and levee banks

Orchard 

Removals

Citrus crops < 3,500 acres, apple crops, pear crops, quince crops, and orchard 

removal matter from a total of 15 acres or less of orchard removal at a single 

location, per calendar year

Vineyard 

Removals Vineyard removal materials from grape and kiwi crops

Surface 

Harvested 

Prunings

Raisin trays (defined as "vineyard materials"), and up to 20 acres of prunings per 

year for almond, walnut, and pecan crops for agricultural operations whose total 

nut acreage at all agricultural operation sites is less than 3,500 acres with a caseby-case allowance of additional burn requests based on economic feasibility

Other 

Materials Diseased beehives

The District will continue to carefully manage all remaining agricultural burning with its 

Smoke Management System (SMS) to ensure that there is no violation the National 

Ambient Air Quality Standards. The District will reevaluate these categories in the next 

evaluation under Rule 4103 when more economic and other data is available.