She's famous for Springwatch, Tomorrow's World and many more shows, but Kate Humble believes her TV career won't last.
As her new science series, Orbit: Earth's Extraordinary Journey, begins on BBC2, she told Radio Times that television careers are always limited.
"TV is a fantastic job but I have never wanted it to be my life," she said. "It's also a job that you have very little control over. It can be all or nothing. At this point I don't know how my year is going to pan out. That's exciting, frustrating and nerve-racking."
Even as she spent a year travelling the world filming her new series, she and her filmmaker husband Ludo Graham have been buying a farm - and she sees that as her future once TV work stops. "The types of TV I'm being asked to do I'd be an idiot to turn down because it's wonderful stuff. But if I get to the stage where I'm not being offered that stuff and it's a choice of being on the telly or on the farm, the farm would win every time.
"The reality is that I'm either not going to want telly or telly is not going to want me. I'm not going to start sobbing into my beer because I'm getting older and old women don't get on the telly. It's just a fact."
Read more about her new series and her new 100-acre farm in the new issue of Radio Times magazine, on sale now.
Kate Humble presents Orbit: Earth's Extraordinary Journey on Sundays at 9:00pm on BBC2 (10:00pm BBC2 Northern Ireland)