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24 maps and charts that explain marijuana

People have been growing and using marijuana for thousands of years. Ancient texts praised the plant for its versatility — it was used for its psychoactive and medical effects and to make clothes and paper. But in 1934, the US effectively banned the plant with strict taxes and regulations — a prohibition that, despite some major changes to the regulatory model, remains to this day. Now, that may be changing: public support for marijuana legalization in the US is at an all-time high. And in 2014, voters in Alaska, Oregon, and Washington, DC, approved legalization. Given the recent shift in momentum, there's perhaps no better time to analyze this plant, where it came from, and what’s next for the policies surrounding it.


    Marijuana and its use

  1. Historical records, Natural History Museum

    How marijuana spread across the world

    Marijuana is believed to have originated in southeast Asia, around modern China. Chinese folklore credits Emperor Shen Nung, who’s often referred to as the father of Chinese medicine, with discovering its medicinal uses, and a Chinese pharmacopoeia from 1500 BC contains references to medical marijuana. The Chinese also used hemp for cloth and paper, and fragments of hemp cloth have been found in ancient Chinese burial grounds. It’s widely believed that marijuana eventually spread through the Middle East to ancient Greece and Rome, before making its way through the rest of Europe, where it was used for hemp fiber, throughout the Middle Ages. After Europeans began to colonize the Americas, marijuana seeds and plants traveled on European ships to South and North America. Hemp was very popular in colonial America; British colonies were required by law to grow hemp, and many of the founding fathers, including George Washington and Thomas Jefferson, grew the plant for its strong fibers.

  2. Marijuana most likely won’t kill you

    There have never been any deaths directly linked to marijuana-caused health effects. An American Scientist analysis found that to fatally overdose, someone would have to take 1,000 times the effective dose (the amount required to get high) of marijuana. In comparison, heroin’s fatal dose was five times its effective dose, alcohol’s was 10, and cocaine’s was 15. It is, in other words, very, very difficult — and perhaps close to impossible — to die from a marijuana overdose. But that doesn’t mean marijuana is perfectly safe. A lot of research has associated teen marijuana use with a range of bad consequences, including cognitive deficiencies and worse education outcomes. Researchers haven’t established that the association is causal, but most generally agree the drug must have some negative effect on the developing teen brain.

  3. Researchers consider marijuana to be safer than alcohol

    British researchers in 2010 sought out to identify the most dangerous drugs, both to society and individuals. They looked at all sorts of variables, including drug-induced health effects, changes in behavior, and impacts on violence and crime. They found the most dangerous drugs were alcohol, heroin, and crack — although alcohol's prominence was partly attributable to how accessible it is, since it’s legal and highly commercialized. Marijuana placed towards the middle of the list. Although there are some problems with the rankings, experts generally agree marijuana is safer than legal substances like alcohol and tobacco.

  4. Marijuana is getting more potent

    The amount of THC, marijuana’s main psychoactive compound, found in pot seized by US law enforcement has greatly increased over the past few decades. This means that someone can now smoke considerably less marijuana to get high — or someone can get much more stoned than might have been possible before. As for why potency is increasing, the most obvious reason is consumer demand: people simply want stronger pot to more quickly reach the effect they desire. Packing more potency into a joint is also beneficial for drug traffickers, since it lets them smuggle smaller portions of the drug, which lowers the chances of getting caught, while making it possible to charge higher prices.

  5. The most frequent pot users are the industry’s best customers

    One study of Colorado's pot market, conducted by the Marijuana Policy Group for the Colorado Department of Revenue, found the top 29.9 percent heaviest pot users in the state made up 87.1 percent of demand for the drug. Drug policy experts worry that this trend encourages the for-profit marijuana industry to market the drug to the most problematic users. Marijuana companies’ "best customers are the problem users," Kleiman said in a previous interview. "They are an industry with a set of objectives that flatly contradicts public interest."


  6. Marijuana's popularity

  7. Marijuana is really popular in the former British colonies

    Several former British colonies — the US, Canada, Australia, New Zealand, and Nigeria — seem to have taken up marijuana at higher rates, alongside Spain and Italy. The US demand for marijuana is a particularly big deal, since it’s what drives the drug flow from South America to Central America to the US — and all the violent drug cartel activity that goes along with the illicit marijuana trade. At several points throughout the war on drugs, federal officials have called on the American public to stop buying illicit drugs so drug cartels no longer have a steady supply of revenue. Americans don’t seem to be listening.

  8. Alaska, Vermont, and Oregon have the most pot users per capita

    Some states enjoy their weed more than others. Two of the three states with the most reported pot users as a percent of the population — Alaska and Oregon — voted to legalize marijuana in November.

  9. How often Americans use pot in a one-minute time span

    Every green blink on this map signifies someone consuming marijuana. To some degree, the map is a reflection of the population in each state. California is the most populous state, so it's little surprise that there's at least one Californian using marijuana each second. Still, it’s remarkable to see just how much Americans are using an illegal substance.

  10. Marijuana use among US teens has been relatively flat

    The number of high school students reporting past-month marijuana use remained relatively flat in the past few years, even as other drug use fell. Drug policy experts attribute these kinds of fluctuations in drug use to cultural shifts, fads, and changing demographics. Surveys show that society as a whole increasingly views marijuana as relatively safe, especially in direct comparisons to tobacco and alcohol. Supporters of marijuana prohibition argue relaxed marijuana laws, such as medical marijuana legalization, have made the drug more accessible to teens. But several studies found no increase in teen marijuana use in states that legalized the drug for medicinal purposes.


  11. Marijuana and the law

  12. Support is growing for legalization

    The latest Gallup poll found 58 percent of Americans now support marijuana legalization. That’s a huge shift: in 1969, 12 percent of Americans were in favor. In response to the growing support, legalization advocacy groups like the Marijuana Policy Project, Drug Policy Alliance, and NORML have backed more efforts to legalize pot at the state level. Voters in 4 states and Washington, DC, have approved the legalization of marijuana.

  13. Millennials really favor legalization

    Nearly seven in 10 millennials support marijuana legalization, according to the Pew Research Center. As Pew’s numbers show, that makes millennials the biggest supporters of legalization. Advocates often tout this trend to argue that the legalization of marijuana is practically inevitable as younger Americans grow up and demand relaxed drug laws from elected officials.

  14. Marijuana is illegal in most states

    More and more states are relaxing marijuana laws, but most still strictly prohibit the drug. The South in particular has zero states with any sort of marijuana dispensaries.

  15. Even hemp is illegal in most states

    Marijuana isn’t only used for its psychoactive effects. The plant was traditionally cultivated for the strong fiber hemp, which can be used to make materials ranging from cloth to paper. But when marijuana prohibition swept the states throughout the early 20th century, the law also stopped industrial hemp production and sales. That ban seems to be coming to an end. In February 2014, President Barack Obama signed a law that allows states to begin experimenting with industrial hemp. In response, 21 states have removed barriers to hemp production.

  16. Europe’s laws for marijuana aren’t much more liberal

    No country in Europe fully allows the production and sale of marijuana. The drug is even illegal in the Netherlands, although the enforcement of such laws, particularly at popular coffee shops, is practically nonexistent. A lot of that can be attributed to international treaties that require European countries to prohibit marijuana. The US is beholden to the same treaties, but states have been granted some flexibility to pass legislation that contradicts federal law. So even as marijuana remains illegal at the federal level, states can allow marijuana for recreational and medical purposes without the US technically defying the boundaries set by international treaties.

  17. Uruguay is the only country where marijuana is known to be fully legal

    Uruguay became the first country to fully legalize marijuana in December 2013, and the law technically took effect in May. But the system could collapse before it gets started. The government expects to begin allowing the sale of pot in late 2014 or sometime in 2015, but a general election in October and the lack of public support for marijuana legalization among Uruguayans could endanger the entire process. Outside of Uruguay, North Korea appears to be the only other country where marijuana could be legal. Several media reports have suggested that there is either no law in North Korea against marijuana or the law is largely unenforced, although, as with many issues related to the Hermit Kingdom, it’s hard to know for sure.


  18. Enforcement against marijuana

  19. Illinois and New York arrest a lot of people for marijuana

    After controlling for the amount of reported marijuana users, New York and Illinois arrested the most people for possessing the drug in 2012. New York decriminalized marijuana in 1977, but the state’s decriminalization law allows arrests for marijuana that’s within public view. Law enforcement in New York City notoriously used this loophole to arrest people, particularly black and Latino men, by getting them to empty their pockets during searches and expose marijuana that would otherwise remain hidden from public view.

  20. Black people are disproportionately arrested for marijuana possession

    roughly 3.7 times more likely to be arrested for marijuana in 2010. Critics of the war on drugs often cite the arrest statistics as evidence that US drug policy is enforced in a racist manner. The disproportionate arrests suggest that marijuana policy is akin to a civil rights issue for poor, minority communities, while more privileged Americans might simply appreciate the convenient ability to legally buy pot at a state-certified dispensary.

  21. The war on marijuana is mostly fought in the West

    Given the huge popularity of marijuana in the US and America’s position as the global leader in the war on drugs, it’s little surprise that most of the marijuana reportedly seized around the world is in the Western Hemisphere. Much of that marijuana is on its way to the US when it’s captured, with production centers in South and Central America shipping the drug all the way up to the US, Canada, and Europe. This illicit drug trade helps fund drug cartels and gangs in Latin America and, as a result, fuels violence in the region. Based on previous studies from the Mexican Institute of Competitiveness and RAND Corporation, marijuana makes up roughly 20 to 30 percent of drug cartels’ revenue.

  22. The US Border Patrol seized nearly 2 million pounds of marijuana in 2011

    Because a lot of marijuana flows through Mexico and into the US, the border plays a huge role in the war on pot. Data from 2011 suggests that literally tons of marijuana were seized, particularly at Texas and Arizona’s borders with Mexico. Unfortunately, the massive illicit drug trade supports criminal organizations and violence along the border. That violence grew particularly bad after 2006, when drug cartels seized entire towns on the Mexican side of the border to guarantee the flow of drugs to the US.

  23. More marijuana is seized at the border than any other drug

    By weight, an overwhelming amount of all drugs seized at the border — more than 99 percent — is marijuana. A lot of this can be attributed to simple economics: a pound of marijuana is much, much cheaper than other drugs, and far more people use pot than cocaine, meth, heroin, and other illicit drugs. But even when controlling for those factors, it seems the US Border Patrol does a much better job capturing marijuana than other illegal substances.


  24. Marijuana and the economy

  25. Marijuana has expanded into a global trade network

    Marijuana is part of a huge global trade network. Along with hashish, a different substance that is also extracted from the marijuana plant, pot flows from all over the world, particularly Latin America and Africa, to North America, Europe, and Oceania. This mostly reflects the ability of people living in developed countries to afford what’s mostly a luxury good, albeit an illegal one. Unfortunately, the profits from this global trade go to criminal organizations that use the money to fund violent operations throughout much of the world.

  26. After the 1980s, the price of marijuana dropped and largely stabilized

    One of the key goals of the war on drugs is to eliminate drug supplies, increase prices as a result, and therefore make drugs a much less affordable habit. When it comes to marijuana, that goal hasn’t been met for decades. After a brief spike in the price of pot in the late 1980s, the price of marijuana dropped and remained relatively stable through 2007. The price is still higher than it was in the early 1980s, but it doesn’t seem like the thousands of tons of marijuana seized over the decades have produced much of an effect on the price of pot in recent years.

  27. Marijuana prices, by state and quality

    The estimated street price for low, medium, and high quality marijuana appeared to drop for most of the country between 2010 and 2013. At the same time, marijuana prices in North Dakota remained stubbornly high. High-quality pot also appears to be cheaper in states with relaxed marijuana laws like California, Colorado, Oregon, and Washington. Beyond that, it’s hard to pull too many state-specific trends from these maps.

  28. Marijuana is becoming a really popular stock

    Over the past two years, investors bid up penny stocks, which are stocks that trade for less than $5 a share, for marijuana from a $500,000 market to more than $7 billion, Bloomberg reported. This reflects the widespread perception that marijuana legalization is only going to spread and, as a result, the legal marijuana market in the US is going to grow. But some people within the industry are highly skeptical. Brendan Kennedy, chief executive officer of the marijuana giant Privateer Holdings, told Bloomberg that the public marijuana companies are "full of shenanigans and charlatans." He added, "Most of them will revert to zero."

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