It could be the title of a specific video channel, a internal project name, or a localized slang term that hasn't gained broad digital traction.
The phrase might be a slight variation of a different term. If you were looking for information on "lava tubes," "mature landscape drainage," or a specific media platform, please provide a bit more context.
It might be a niche description for ancient lava tubes, established subterranean root systems, or specialized irrigation piping ("land tube") used in mature landscapes.
If you can describe what a "mature land tube" does or where you encountered the term, I can provide a more detailed write-up.