11 tons of trash left after San Francisco 420 smokeout

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Thousands Light Up For 4/20

SAN FRANCISCO (Reuters) -- Thousands of marijuana enthusiasts who joined a massive smokeout on "Hippie Hill" in San Francisco's Golden Gate Park to celebrate the informal pot holiday named 4/20 left behind 11 tons of trash, officials said on Thursday.

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About three dozen staff worked into Wednesday night after the event and were back out at the park cleaning up on Thursday morning after the event, San Francisco Recreation and Parks Department spokesman Joey Kahn said.

The date of April 20, or 4/20, corresponds with the numerical figure widely recognized within the cannabis subculture as a symbol for all things marijuana.

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11 tons of trash left after San Francisco 420 smokeout

Alabama

No legalization of any kind

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Alaska

Marijuana legalized for medical and recreational use 

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Arizona

Marijuana legalized for medical use

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Arkansas

No legalization of any kind 

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California

Marijuana legalized for medical use

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Colorado

Marijuana legalized for medical and recreational use  

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Connecticut

Marijuana legalized for medical use 

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Delaware

Marijuana legalized for medical use 

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Florida

No legalization of any kind

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Georgia

No legalization of any kind

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Hawaii

Marijuana legalized for medical use

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Idaho

No legalization of any kind

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Illinois

Marijuana legalized for medical use

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Indiana

No legalization of any kind

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Iowa

No legalization of any kind

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Kansas

No legalization of any kind

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Kentucky

No legalization of any kind

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Louisiana

No legalization of any kind

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Maine

Marijuana legalized for medical use

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Maryland

Marijuana legalized for medical use

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Massachusetts

Marijuana legalized for medical use

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Michigan

Marijuana legalized for medical use

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Minnesota

Marijuana legalized for medical use

(photo: anthonylibrarian/Flickr)

Mississippi

No legalization of any kind

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Missouri

No legalization of any kind 

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Montana

Marijuana legalized for medical use

(photo: J.Stephen Conn/Flickr)

Nebraska

No legalization of any kind 

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Nevada

Marijuana legalized for medical use

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New Hampshire

Marijuana legalized for medical use

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New Jersey

Marijuana legalized for medical use 

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New Mexico

Marijuana legalized for medical use 

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New York

Marijuana legalized for medical use

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North Carolina

No legalization of any kind

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North Dakota

No legalization of any kind

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Ohio

No legalization of any kind

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Oklahoma

No legalization of any kind

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Oregon

Marijuana legalized for medical and recreational use  

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Pennsylvania

No legalization of any kind

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Rhode Island 

Marijuana legalized for medical use

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South Carolina

No legalization of any kind

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South Dakota

No legalization of any kind

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Tennessee

No legalization of any kind

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Texas

No legalization of any kind

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Utah

No legalization of any kind 

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Vermont

Marijuana legalized for medical use

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Virginia

No legalization of any kind

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Washington

Marijuana legalized for medical and recreational use 

(photo: Shutterstock)

West Virginia 

No legalization of any kind

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Wisconsin

No legalization of any kind 

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Wyoming

No legalization of any kind

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According to the marijuana magazine High Times, the concept of 4/20 originated in the early 1970s, as a group of teenagers in the Bay Area city of San Rafael used it as code to gather after school and smoke the plant.

Some 5,000 more pounds of trash were left this year compared to last year's event, he said. Kahn said he expected the costs to the department for the event to reach around $50,000.

The San Francisco Police Department, who were out in force both with uniformed and plain clothes officers, recorded eight arrests at the event and doled out 35 traffic-related citations.

The long-running Bay Area tradition, which authorities closely monitor, could mark the last such observance while recreational marijuana remains illegal under state law in California. Medical marijuana is legal in the state with a doctor's recommendation.

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Voters will likely decide in November whether to approve a ballot measure that would legalize adult possession for recreational purposes.

The distinct odor of marijuana smoke mixed with the smell of barbecue in a gentle breeze wafting over an estimated 15,000 attendees enjoying the sunny Wednesday afternoon.

Marijuana, once widely demonized in the United States, has seen growing acceptance in recent years, especially among younger, more liberal Americans.

Although cannabis remains classified as an illegal narcotic under federal law, two dozen U.S. states have approved marijuana for medical purposes since California became the first to do so in 1996.

Since 2012 recreational use of the drug has been legalized in Colorado, Washington state, Oregon, Alaska and the District of Columbia.

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11 tons of trash left after San Francisco 420 smokeout
KITTREDGE, CO - MARCH 9: Scott Hello ties limbs of a High CBD hemp plant up to help sustain vertical growth at Ambary Gardens in Kittredge, Colorado on March 9, 2016. Arvada has approved a hemp growing operation for cultivation of CBD oil. A surprising move as Arvada has declined to license recreational or medical marijuana shops. (Photo by Seth McConnell/The Denver Post via Getty Images)
KITTREDGE, CO - MARCH 9: An employee displays trimmed bud from a High CBD hemp strain at Ambary Gardens in Kittredge, Colorado on March 9, 2016. Arvada has approved a hemp growing operation for cultivation of CBD oil. A surprising move as Arvada has declined to license recreational or medical marijuana shops. (Photo by Seth McConnell/The Denver Post via Getty Images)
DENVER, CO - FEBRUARY 26: John Fritzel owns four marijuana businesses. He was on the grass couch at Buddy Boy Brands in Denver on Friday, February 26, 2016. He is one of the top businessmen in the marijuana industry in Denver. (Photo by Cyrus McCrimmon/ The Denver Post)
A pedestrian crosses a street in downtown Pueblo, Colorado, U.S., on Thursday, Feb. 25, 2016. About 938 dispensaries, which outnumber Starbucks in Colorado, in 2015 yielded $135 million in state taxes and fees, 44 percent more than a year earlier. Yet as the market enters its third year after voters legalized retail sales in 2012, officials question whether the newfound income outweighs the escalating social costs. Photographer: Matthew Staver/Bloomberg via Getty Images
Marijuana plants grow in a greenhouse at the Los Suenos Farms facility in Avondale, Colorado, U.S., on Thursday, Feb. 25, 2016. About 938 dispensaries, which outnumber Starbucks in Colorado, in 2015 yielded $135 million in state taxes and fees, 44 percent more than a year earlier. Yet as the market enters its third year after voters legalized retail sales in 2012, officials question whether the newfound income outweighs the escalating social costs. Photographer: Matthew Staver/Bloomberg via Getty Images
Marijuana plants grow in a greenhouse at the Los Suenos Farms facility in Avondale, Colorado, U.S., on Thursday, Feb. 25, 2016. About 938 dispensaries, which outnumber Starbucks in Colorado, in 2015 yielded $135 million in state taxes and fees, 44 percent more than a year earlier. Yet as the market enters its third year after voters legalized retail sales in 2012, officials question whether the newfound income outweighs the escalating social costs. Photographer: Matthew Staver/Bloomberg via Getty Images
Manager Ross Phillip stakes marijuana plants in a flower room at the grow facility for Sense of Healing dispensary in Denver, Colorado, U.S., on Wednesday, Dec. 9, 2015. The $3.5 billion U.S. cannabis market is emerging as one of the nation's most power-hungry industries, with the 24-hour demands of thousands of indoor growing sites taxing aging electricity grids and unraveling hard-earned gains in energy conservation. Photographer: Matthew Staver/Bloomberg via Getty Images
LOUISVILLE, CO - NOVEMBER 12: Ajoya is a new marijuana dispensary in Louisville, CO and it's interior space offers a new retail experience for customers. The interior was designed by Roth Sheppard Architects. Marty Lucas works the counter as she fills a boutique shopping bag. Photos of the colorful space on Thursday, November 12, 2015. (Photo by Cyrus McCrimmon/The Denver Post via Getty Images)
LEADVILLE, CO - JUNE 12, 2015: Novelty burlap 'marijuana bags' for sale at an antique shop in Leadville, Colorado. The fake bags are sold throughout Colorado where the purchase and use of recreational marijuana is legal. (Photo by Robert Alexander/Getty Images)
FORT LUPTON, CO - JUNE 10: PureVision Technology president Ed Lehrburger dumps a bag of industrial hemp onto a table to show its similarity to marijuana (in look only) on Wednesday, June 10, 2015. PureVision Technology Inc., a Fort Lupton biofuels company that is processing hemp stalks into sugars, lignin, pulp and CBD extracts. (Photo by AAron Ontiveroz/The Denver Post via Getty Images)
DENVER CO - APRIL 20: Pot smokers partake in smoking marijuana at exactly 4:20 during the annual 420 celebration in Lincoln Park near the State Capitol in Denver, Colorado on April 20, 2015. (Photo By Helen H. Richardson/ The Denver Post)
AURORA, CO - April 23: 'Headband' a strain of Wednesday, April 23, 2015 at Good Chemistry in Aurora, Colorado. The shop which opened in early April is one of many that have popped up in the Aurora over the last six months of beginning of recreational marijuana in the city. (Photo By Brent Lewis/The Denver Post via Getty Images)
A worker at a dispensary handles bags of marijuana delivered by the courier service CannaRabbit LLC in Louisville, Colorado, U.S., on Friday, March 27, 2015. CannaRabbit and peers are rushing in as regional truckers and nationwide haulers United Parcel Service Inc. and FedEx Corp. steer clear of transporting marijuana on concerns over the lack of nationwide clearance of a practice that is still illegal in most states. Photographer: Matthew Staver/Bloomberg via Getty Images
DENVER, CO - MARCH 11: A sample of marijuana is in a jar, for customer to look at and smell, at Euflora Dispensary in Denver, March 11, 2015. Colorado pot sales soar to record in January, bringing $2.3 million for schools. Around $36.4 million of recreational marijuana was sold this January compared to about $14.69 million sold the same month last year. (Photo by RJ Sangosti/The Denver Post via Getty Images)
DENVER, CO - MARCH 11: Robert Grandt works in the grow room at 3D Cannabis Center in Denver, March 11, 2015. Colorado pot sales soar to record in January, bringing $2.3 million for schools. Around $36.4 million of recreational marijuana was sold this January compared to about $14.69 million sold the same month last year. (Photo by RJ Sangosti/The Denver Post via Getty Images)
In this Feb. 10, 2016 photo, marijuana sits on a scale next to one-gram containers designed to look like shotgun shells, at Smokin Gun Apothecary, the new marijuana dispensary, in Glendale, Colo., a home rule municipality just outside downtown Denver. Smokin Gun Apothecary is on a site formerly occupied by the Denver areaâs best known strip club, Shotgun Willieâs. The strip club hasnât gone away, itâs moved just across the parking lot. Both businesses have the same owner, who envisions pot shoppers getting discounted drinks at the strip club and is outfitting the roof of the pot shop for a future lounge in case Colorado changes its law banning on-site marijuana consumption. (AP Photo/Brennan Linsley)
This Friday, Dec. 18, 2015, photograph, shows the logo on the front of jars of marijuana buds marketed by rapper Snopp Dogg in one of the LivWell marijuana chain's outlets south of downtown Denver. LivWell grows the Snoop pot alongside many other strains on its menu. (AP Photo/David Zalubowski)
FILE - In this May 8, 2014 file photo, a customer pays cash for retail marijuana at 3D Cannabis Center, in Denver. A year after Colorado's marijuana tax for schools came in far short of its goal, the fund is setting records and has accrued more money in the first five months in 2015 than it did for all of 2014. (AP Photo/Brennan Linsley, File)
DENVER, CO. - DECEMBER 06: Beth Bice of Charlotte, NC smokes a joint on the bus during a marijuana tour hosted by My 420 Tours in Denver, CO on December 06, 2014. Bice saw a video advertising the tours and said, 'lets go to Colorado.' She explained, 'Im not a big drinker. So to do this and find people like me it feels awesome. Its a movement, you want to be a part of it. The more and more people that get on board with this, the more and more acceptable it will become. During the day tourists visited La Conte's grow facility, La Conte's Clone Bar & Dispensary, Native Roots dispensary and Illuzions Glass Gallery. (Photo By Craig F. Walker / The Denver Post)
DENVER, CO. - DECEMBER 06: Mike Goldstein of New York, NY photographs himself with plants at La Conte's grow facility during a marijuana tour hosted by My 420 Tours in Denver, CO on December 06, 2014. During the day tourists visited La Conte's grow facility, La Conte's Clone Bar & Dispensary, Native Roots dispensary and Illuzions Glass Gallery. (Photo By Craig F. Walker / The Denver Post)
DENVER, CO - AUGUST 13: Steve Herin, Master Grower at Incredibles, works on repotting marijuana plants in the grow facility on Wednesday, August 13, 2014 in Denver, Colorado. Higher than expected demand for marijuana edibles is pushing several Colorado manufacturers, like Incredibles, to expand their operations. (Photo by Kent Nishimura/The Denver Post via Getty Images)
TELLURIDE, CO - JULY 8, 2014: A sign in the window of one of several medical and recreational marijuana retail stores in Telluride, Colorado, advertises its locally grown products. (Photo by Robert Alexander/Getty Images)
DENVER, CO - JUNE 27: Kayvan Khalatbari is an entrepreneur in Denver. He was photographed on Friday, June 27, 2014 inspecting a strain at Denver Relief. He owns the Sexy Pizza chain, Denver Relief, and founded Sexpot Comedy. He has gained famed by donning a chicken suit (bought online) and mocking Governor John Hickenlooper, for promoting beer but not marijuana. (Denver Post Photo by Cyrus McCrimmon)
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