Does this look okay?

[Brontosaurus]

This is a Parodia leninghausii that my friend owns, and I'm a little worried at how little green it shows. Is it normal/okay that it has such a brown stem? If not, what should I do? Thanks!

[StarDragon]

How old are those? The discoloration on the stems resembles corking, but I don't know if it naturally goes that far up the stem on that species. Are those golden ball cacti? From what little I can see on the tops, that part appears healthy, & if the discoloration on the stems is corking, then it appears normal.

[greenknight]

That's way more than normal corking. I don't know what would cause that, though, but the first rule is check the roots.

[StarDragon]

I forgot to mention, I once had a rose quartz cactus that had red spider mites that scarred it from the base up. Also, the only reason I mentioned the idea that it may be corking, is because I have seen photos of old cacti with corking relatively far up the stems. As I said, I don't know how far normal corking goes on what appears to be a golden ball cactus. I said, IF its corking, then it appears normal. Just wanted to clear that up, by no means am I an expert, I'm just going by what I do know.

[greenknight]

Check for mites as well. If these were really old it would be one thing, but this species gets much larger - if those are very old plants, then their growth has been seriously suppressed. Take a look at the gallery here - http://davesgarden.com/guides/pf/go/64102/

[Brontosaurus]

I didn't see any mites. What should I check the roots for?

[greenknight]

Check to see if it has any roots - and if the roots are healthy. Are they infested with root mealy bugs? Is there a ball of old dried-out peat around the roots?

[Brontosaurus]

I checked out the roots, they look fine to me. The cactus was kind of neglected before I took it over. I think maybe it just wasn't getting what it needed for a while and that's why is discolored. Is that possible?

[greenknight]

That's very possible - more than possible, it's the most likely explanation since you've eliminated the other usual causes. Normally a fast-growing species, this may just be how it adapted to hard times.