When it comes to today's cannabis icons, few are bigger than Woody Harrelson, who has narrated the pro-marijuana legalization documentary 'Grass' (1999), protested hemp prohibition by planting seeds illegally, and smoked up on screen in movies like 'Zombieland' (2009). But after decades of overdoing it, Harrelson has given up pot so that he can learn moderation.

"I actually stopped smoking pot almost a year ago," Harrelson recently told Abraham Riesman of Vulture. He explained that he needed a break after "30 solid years of just partying too fucking hard."

But even though they're splitting up, Harrelson said he doesn't have any hard feelings for Mary Jane. "I don’t have a problem at all with smoking. I think it’s great. I think it’s a great drug," he added.

Of course, there's lots of temptation for a celebrity with his standing in cannabis culture. "[L]ast night, someone had — not just good herb but sativa; really good sativa. There’s a joint, and beautifully rolled. I like a beautifully rolled … and I just was like, I mean, I’ve gone this long. It would be weird to just be like, Okay, let me have a hit off that,' and then suddenly go back to smoking too much," he said.

So it looks like Seth Rogen and James Franco will have to come up with a new plot for the sequel to 'Pineapple Express'.