Alan Jackson released his first studio album in 1990, and in the 25 years since, he's seen a lot happen in the country music industry. He's also recorded and performed plenty of songs -- some of which he doesn't really remember.

"Sometimes, a fan will come up and mention an album cut, and I can hardly remember it," the country legend tells Billboard. "I've cut several hundred songs, and even some of the ones I've written, I've forgotten about."

Jackson knows it's natural for him to have forgotten about a few tracks, even if they are favorites for some of his fans, but he's been on the other side of the situation, too, and he says that it doesn't feel great to have an artist forget about a song that means a lot to you.

"I wouldn't feel bad about that, but years ago, Merle Haggard did some shows with me, and we were all in awe of him. He was doing soundcheck, and the band and I were out there just drooling over him. We said, 'Merle, how about doing this song?' He sat there, thought a minute, and couldn't remember it, and it was one he wrote," Jackson recalls. "I couldn't believe it. And, now, I'm the same way."

Jackson is preparing to release his 21st studio album, Angels and Alcoholon July 17. He recently shared a new single off of the project, "Jim and Jack and Hank," which gives a humorous look at a breakup. Jackson wrote the track solo, something that he says that he's been doing a lot more of lately.

“I’ve been doing that for a few years now,” Jackson says. “When I got started on Music Row, I would write with different writers. Then, once my career took off, I was gone all the time — playing a couple hundred shows a year. You weren’t home long enough to wash your clothes. I ended up writing a lot by myself, and it just kind of stayed that way.”

"Jim and Jack and Hank" is one of seven songs that Jackson wrote for the new album. Angels and Alcohol is available for pre-order on Amazon.

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