As the sky grew darker the conversation became increasingly heated, flipping from religion to jobs to local politics. Suddenly, one of the men paused and turned in his chair. "See, it is the green leaf," he said, explaining the unusually animated discussion as he pinched a few more leaves together and tossed them into his mouth.
But in the United States khat is illegal, and an increased demand for the plant in cities such as Washington and San Diego is leading to stepped up law enforcement efforts and escalating clashes between narcotics officers and immigrants who defend their use of khat as a time-honored tradition.
In the last few years, San Diego, which has a large Somali population, has seen an almost eight-fold increase in khat seizures. Nationally, the amount of khat seized annually at the country's ports of entry has grown from 14 metric tons to 55 in about the last decade.
"It is a very touchy subject. Some people see it like a drug; some people see it like coffee," said Abdulaziz Kamus, president of the African Resource Center in Washington, D.C. "You have to understand our background and understand the significance of it in our community."
Increased immigration from countries such as Ethiopia, Yemen and Somalia has fueled the demand in this country and led to a cultural conflict.
"We grew up this way, you can't just cut it off," said a 35-year-old Ethiopian medical technician between mouthfuls of khat as he sat with his friends in the office.
In the Horn of Africa and parts of the Middle East, khat is a regular part of life, often consumed at social gatherings or in the morning before work and by students studying for exams. Users chew the plant like tobacco or brew it as a tea. It produces feelings of euphoria and alertness that can verge on mania and hyperactivity depending on the variety and freshness of the plant.
But some experts are not convinced that its health and social effects are so benign. A World Health Organization report found that consumption can lead to increased blood pressure, insomnia, anorexia, constipation and general malaise. The report also said that khat can be addictive and lead to psychological and social problems.
"It is not coffee. It is definitely not like coffee," said Garrison Courtney, spokesman for the Drug Enforcement Administration. "It is the same drug used by young kids who go out and shoot people in Africa, Iraq and Afghanistan. It is something that gives you a heightened sense of invincibility, and when you look at those effects, you could take out the word 'khat' and put in 'heroin' or 'cocaine'."
Khat comes from the leaves and stems of a shrub and must be shipped in overnight containers to preserve its potency. It contains the alkaloid cathinone, similar in chemical structure to amphetamine but about half as potent, according to Nasir Warfa, a researcher in cross cultural studies at Queen Mary University of London.
The United Kingdom determined last year that evidence does not warrant restriction of khat. In the United States, the substance has been illegal under federal law since 1993.
But the world supply of khat is exploding. Countries such as Ethiopia and Kenya now rely on it as a major cash crop to bolster their economies. Khat is Ethiopia's second largest export behind coffee.
Khat usage has grown so much in San Diego that Assemblyman Joel Anderson (R-San Diego) wrote a 2008 bill that added cathinone and its derivative cathine to California's list of Schedule II drugs along with raw opium, morphine and coca leaves.
As of Thursday, Anderson's bill made possession of khat a misdemeanor in California, punishable by up to one year in county jail and a $1,000 fine. Possession of the leaf with intent to sell is a felony that carries a three-year maximum sentence in state prison.
In some cases, khat seizures have resulted in warnings and probation. In other instances, like New York City's "Operation Somali Express" bust in 2006, which led to the seizure of 25 tons of khat worth an estimated $10 million, the perpetrators were sent to jail for up to 10 years.
"In my mind, [such arrests are] wrong," said an Ethiopian-born cabdriver who was arrested in November in a Washington, D.C., khat bust and spoke on condition of anonymity. "They act like they know more about khat than I know."
Khat leaves are sold attached to thick stalks or dried like tea leaves. A bundle of 40 leafed twigs costs about $28 to $50.
The plant's cost has been linked to family problems, including domestic abuse, said Starlin Mohamud, a Somali immigrant who is completing a dissertation on khat at San Diego State University.
In fact, within the East African community in the U.S., there are many who welcome the khat restrictions.
"I have seen what it does," Mohamud said. "Families who are trying to make ends meet on a daily basis cannot afford it. It just creates so many problems between a husband and wife to the point where a broken family is going to be the result."
Not all lawmakers, however, support the increased efforts to prosecute khat sellers and users. California state Sen. Gloria Negrete McLeod (D-Chino) called khat use "a minor problem that may be nonexistent and little understood" and voted against Anderson's bill.
"The Legislature cannot continue to add on penalties and punishments filling up critically overcrowded prison system without weighing the consequences on how this will affect California," she said.
Even though khat smuggling continues to grow in the United States, the level is nowhere near that of drugs like marijuana, cocaine, heroine and methamphetamine. Still, law enforcement officials worry that in a refined, stronger and more portable form, khat could spread outside the immigrant communities.
In Israel, a pill known as hagigat (essentially Hebrew for "party khat"), has emerged on the club scene.
"I don't think we are going to see American teenagers chewing the plant," said Phil Garn, a U.S. postal inspector in San Diego. "But based on what I saw with meth and how it spread across the country, I can absolutely see how khat in a refined form could be a major problem."