Current issue and featured articles
INTRODUCTIONSpecial Issue: Cannabis
In this special issue, California Agriculture presents research articles on cannabis production, the economics of California's cannabis industry, and the social and community impacts of cannabis.
INTRODUCTIONCalifornia cannabis regulation: An overview
In 2016, Proposition 64 decriminalized the possession and use of cannabis by anyone in California aged 21 or over. But the 2015 Medical Marijuana Regulation and Safety Act had begun the process of regulating cannabis in the state.
INTRODUCTIONA concise cannabis guide: History, laws and regulations
An overview of key cannabis laws and regulations in California.
NEWSRestrictions and opportunities for UC cannabis research
Cannabis is legal in California but illegal in the United States. The plant's ambiguous status cuts off many avenues of cannabis research — but leaves other approaches wide open.
RESEARCH NEWSThe rapid evolution of UC cannabis research
At campuses across the UC system, cannabis researchers are grappling with questions that have accompanied legalization.
CONVERSATIONCalCannabis: Regulating a previously unregulated industry
An interview with Richard Parrott, Director of the California Department of Food and Agriculture's CalCannabis Cultivation Licensing Division.
CONVERSATIONScience and law enforcement teaming up to help “critters”
An interview with Scott Bauer, Senior Environmental Scientist, California Department of Fish and Wildlife
CONVERSATION“Like every other industry” — An on-the-ground perspective on Proposition 64
An interview with Amanda Reiman, Vice President of Community Relations, Flow Kana
Peer-reviewed research and review articles
First known survey of cannabis production practices in California
Most growers in this survey produced their crop outdoors or in greenhouses, relied primarily on groundwater, used biologically based inputs for pest management and employed seasonal workers paid at fixed piece rates.
Legalization of cannabis production has daylighted a unique and highly valuable crop in California agriculture. State and regulatory agencies must now address the ecological, social and agricultural effects of cannabis production, but little is known about how growers produce this crop. Using an online survey, we gathered information from growers in July 2018 on their production practices. According to responses from about 100 growers, most cannabis was produced outdoors or in greenhouses, relied primarily on groundwater and used biologically based inputs for pest management. Many farms employed seasonal workers paid at fixed piece rates. Regulatory compliance varied according to farm size. Beginning to document growing practices will help scientists formulate key environmental, social and agronomic questions and develop relevant research and extension programs to promote best management practices and minimize negative environmental impacts of production.
Characteristics of farms applying for cannabis cultivation permits
In Humboldt County, larger and faster-growing cannabis farms apply for permits at higher rates than do smaller or slower-growing farms.
Cannabis producers in California can now participate in a regulated supply chain — but little is known, despite considerable speculation, about which types of producers are likely to seek legal status. Growers' decisions about joining the legal market are central to questions about how formalization will transform cannabis production in California, and in particular whether small farms, which were encouraged under Proposition 64, can remain part of the industry. We combine data on the location and characteristics of cannabis farms in 2012 and 2016 with applications for cultivation permits from 2018 to investigate farm characteristics associated with cannabis formalization in Humboldt County. We find strong evidence that the farms most likely to start the permit process are larger, existed in 2012 prior to the start of the “green rush” and expanded at greater rates between 2012 and 2016. The evidence is consistent with concerns that formalization of the cannabis industry may lead to industry consolidation, as has been the trend in California's agricultural and timber industries more broadly.
Retail cannabis prices in California through legalization, regulation and taxation
A study investigates price patterns at California cannabis retailers during a period of major regulatory changes.
Traditional sources of retail price information, such as scanner data and government price surveys, are not available for cannabis. To help fill this gap, between October 2016 and July 2018 the UC Agricultural Issues Center collected online retail price ranges for dried cannabis flower and cannabis-oil cartridges at retailers around California. During this 21-month time period, the legal landscape of the California cannabis market underwent three broad regulatory changes: adult-use decriminalization, licensing and regulation and mandatory testing. This article provides unique primary data on legal cannabis prices in California before and after each of these three changes. Our data are imperfect but do provide a glimpse of the patterns of California cannabis prices at different times. For dried cannabis flower, we observe relatively stable retail prices over the 21-month period at both the top and bottom ends of the price range. For cannabis-oil cartridges, we observe relatively stable prices at the bottom end but increasing prices at the top end between November 2017 and July 2018.
Watering the Emerald Triangle: Irrigation sources used by cannabis cultivators in Northern California
Reported subsurface water use among North Coast cannabis cultivators is widespread and may become increasingly common.
Water use by cannabis cultivators represents an emerging threat to surface flows in Northern California's sensitive watersheds. To date, however, no data has been available to formally assess where cannabis sites source their water. This study analyzed data from annual reports, covering the year 2017, submitted by 901 cannabis cultivators enrolled in the Cannabis Waste Discharge Regulatory Program administered by the North Coast Regional Water Quality Control Board. The analysis identified cannabis cultivators' most common sources for water extraction, monthly patterns for each water source and differences between sites compliant and not compliant with the cannabis program. The most commonly reported source of water was wells (58% of sites), with most extraction from wells occurring during the growing season (April through October). Surface water diversions (22% of sites) and spring diversions (16% of sites) were the most common sources after wells, with extractions from these sources distributed much more evenly across the year. Although nearly one-third of noncompliant sites (33%) used wells, this source was more than twice as frequently reported among compliant sites (68%), indicating that wells may become increasingly common as more sites become part of the regulated cannabis industry.
Costs of mandatory cannabis testing in California
California's safety standards for cannabis — compared to standards in other states and to standards for food products in California — are tight.
Every batch of cannabis sold legally in California must be tested for more than 100 contaminants. These contaminants include 66 pesticides, for 21 of which the state's tolerance is zero. For many other substances, tolerance levels are much lower than those allowed for food products in California. This article reviews the state's testing regulations in context, including maximum allowable tolerance levels — and uses primary data collected from California's major cannabis testing laboratories and several cannabis testing equipment manufacturers, as well as a variety of expert opinions, to estimate the cost per pound of testing under the state's framework. We also estimate the cost of collecting samples, which depends on the distance between cannabis distributors and laboratories. We find that, if a batch fails mandatory tests, the value of cannabis that must be destroyed accounts for a large share of total testing costs — more than the cost of the tests that laboratories perform. Findings from this article will help readers understand the effects of California's testing regime on the price of legal cannabis in the state — and understand how testing may add value to products that have passed a series of tests that aim to validate their safety.
Perceptions of cannabis among Humboldt County timberland and ranchland owners
A Humboldt County survey investigates traditional agriculturalists' views on cannabis cultivation.
Cannabis is often grown on agricultural and forest lands in California, but little is known about the adjustments that traditional agriculture and timber producers are making to their livelihoods as cannabis becomes legal under state law. Our goal in this research was to better understand how larger landowners, whose families have often produced timber and cattle for generations, are experiencing increased cannabis production in their areas — and also to better understand these landowners' perceptions of the impacts of cannabis, whether positive or negative, on their communities. To accomplish this, we surveyed landowners who owned at least 500 acres in Humboldt County, an area that — more than 40 years ago — became one of the first California counties to begin experiencing expansive cannabis cultivation. Of the 211 landowners we invited to complete a survey, 71 responded, providing insights into their experiences with and perceptions of cannabis production. Many survey respondents reported illegal cultivation on their properties, problems with shared roads and other direct negative effects of cannabis production. Most landowners also reported that cannabis production has increased the cost of labor, though they acknowledge that it has increased the value of their property as well. Survey respondents, however, have not changed their views of cannabis with legalization. The findings of this study illustrate some of the challenges involved in developing land use ordinances and other policies that can support multiple industries whose interests may be in competition.
“We can't just be a county that supports inebriants”: Voices of the noncannabis agricultural community
Interviews with noncannabis producers in Northern California revealed a variety of concerns about legal cannabis production, from access to land and crop shifts to outsider investments.
Legalized recreational cannabis poses uncertainty and challenges for the noncannabis agricultural and ranching community in Northern California, including what it might mean in terms of the price of farmland and ranchland and the effects on the regional culture of diverse crop production. In-depth interviews in Humboldt, Mendocino and Sonoma counties with noncannabis farmers, ranchers and key individuals closely tied to the community revealed insight and an overarching concern about the future for noncannabis producers in those counties. The research was conducted in the summer and fall of 2017, when the state and counties were ramping up development and implementation of recreational cannabis cultivation policies. Interviewees expressed concern about land prices, potential crop shifts, and outside investment in the cannabis sector, and recognized the parallels and emerging alliances between wine and cannabis producers. They also identified opportunities for diversifying their production and for improving the environmental impacts of cannabis production.
Growers say cannabis legalization excludes small growers, supports illicit markets, undermines local economies
The survey sample was small, but results suggest regulations may need to be modified to incentivize grower participation in state licensing programs.
In 2018, we surveyed cannabis growers about their experiences with California's commercial cultivation legalization system. Our results suggest high rates of noncompliance with the new regulations. Of the respondents, 31% reported income from cannabis and had not applied for cultivation licenses, indicating a violation of state regulations. These findings highlight the need to further explore conditions that might incentivize growers to apply for cultivation licenses. Respondents' answers and comments indicate modifications to cannabis cultivation licensing programs might be needed to reduce compliance costs and regulatory inconsistencies and to overcome threats of legal repercussions from enhanced bureaucratic oversight. Growers characterized legalization as a process that excludes small growers, contributes to an increase in black market sales and undermines the economies in rural communities. More research is necessary, including on the socioeconomic and environmental contributions that unlicensed small cannabis growers make to rural regions.
Cannabis farmers or criminals? Enforcement-first approaches fuel disparity and hinder regulation
Siskiyou County, and many other counties, chose not to recognize cannabis cultivation as agriculture. This ethnographic study reveals the effects on parity in farmer rights and access to resources.
Since California's cannabis legalization, localities have played a central role in determining the regulatory terms of where, how and within what legal bounds cannabis cultivation occurs. Siskiyou County, a rural, conservative and majority white county in Northern California, chose not to recognize cannabis cultivation as agriculture. It drew up highly restrictive cannabis cultivation regulations, largely under the purview of law enforcement rather than civil agencies. Hmong-American cultivators, made highly visible through enforcement practices, policy forums and media discourses, have borne the brunt of this regulatory regime. Cannabis policy, especially in its ethnic-racial dimensions, has become symbolic of broader anxieties about cultural and agricultural change. We employed ethnographic methods to research the formation and enforcement of Siskiyou's restrictive cannabis cultivation regulations, and their differential effects across local populations. We found that the county's law enforcement–first regulatory approach blurred civil and criminal lines, made some cultivators more visible and vulnerable to enforcement, and promoted criminalizing approaches to cultivators, even among civil regulatory agencies. These developments hinder the ability of agencies (including the California Department of Food and Agriculture and the California Department of Fish and Wildlife) to ameliorate negative social and ecological effects of cannabis cultivation through civil regulation, support and services.
FeaturedCover crops prove effective at increasing soil nitrogen for organic potato production
Organic crops command high wholesale prices, but organic management of nutrient deficiencies and pests can be a challenge.
Many farms in northeast California are experimenting with organic production to take advantage of price premiums and niche markets. A common challenge in organic farming is finding dependable nitrogen sources to meet the needs of vegetable and grass crops, especially in fields with low soil nitrogen. This study assessed the use of cover crops and organic amendments for increasing soil nitrogen for potato production at the Intermountain Research and Extension Center in Tulelake. Researchers evaluated several cover crop species, three planting dates and multiple cover crop mixes. Amendments included composts, manures, bloodmeal and soymeal. The data collected in the study included total nitrogen from cover crops and amendments, plant-available nitrogen in the soil, potato petiole nitrate and crop yield and quality. Vetches and field peas, managed as green manure, were successful at satisfying potatoes' in-season nitrogen demand. These cover crops, grown alone or in mixes with non-legume species, produced potato crops whose yield and quality were similar to crops grown with conventional fertilizers. The cover crops' influence on potato pest pressure was neutral. Chicken manure was the most cost-effective amendment for satisfying potatoes' in-season nitrogen demand.
FeaturedRatio of farmworkers to farm jobs in California increased to 2.3 in 2016
The ratio of workers to average jobs is increasing, moving the farm labor market away from what public policy has long tried to achieve, a farm labor market with fewer workers who are employed most of the year.
California Employment Development Department data suggest that almost 5% of California's workers were employed in agriculture, in 2016. In that year, monthly average employment in agriculture was 425,400, but the number of workers with at least one job in agriculture was 2.3 times that figure, 989,500. The number of hired farmworkers, including supervisors and office personnel, rose almost 20% between 2015 and 2016. Most workers employed in agriculture do not work year-round, so there is a gap between the average earnings of a full-time equivalent job in agriculture ($32,316 in 2016) and the average earnings of actual agricultural workers ($19,800 in 2016). This gap was widest for the third of all farmworkers employed by farm labor contractors (FLCs). Over half of the workers whose maximum earnings were in agriculture had only one farm job. Almost 20% of farmworkers received unemployment insurance benefits in 2016, including half of those whose maximum earnings were in logging and cotton ginning. Public policy has long favored a farm labor market in which most workers are employed year-round; these data indicate that the farm labor market in California is, on average, heading in the opposite direction.
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