In an extensive interview with Rolling Stone, Crazy Horse guitarist Frank 'Poncho' Sampedro expresses some concerns that Crazy Horse's current tour with Neil Young may be their last.

As the baby of the band at 64 years old, Sampedro acknowledges that the health of the Crazy Horse members, as well as Young himself, will ultimately dictate how much longer the band continues to perform.

"I just think once it stops it's going to be kind of hard to get it rolling again," he says on the phone from his home in Hawaii. "My gut tells me this is really the last tour. I hate saying their ages, but I'm 64 and I'm the baby of the band. I love playing and we're playing as good as we ever did, but at any time something could go down with any one of us."

There has been a flurry of activity in the Neil Young and Crazy Horse camp over the last year. After not having worked together for almost a decade, the longtime cohorts released two full-length records last year -- 'Americana' and 'Psychedelic Pill' -- and have been touring the world since last August. Sampedro says that many of the group's shows are extending well beyond the two-and-a-half-hour mark.

"Our shows are physical," he states. "It takes a lot of energy to play that much. It just seems at some point something is going to break. I already had an operation on my thumb. Neil's wrist bugs him, and he has to tape it when he plays. You can't fool time. You can't count on this happening again in five years."

Next up on Neil Young and Crazy Horse's tour schedule is a ten-show run through Europe, beginning on June 2 in Germany and wrapping up on June 17 in England.