Corrupted textures

Hi, I am using Xcode and objective-C, with OpenGL ES. I was just wondering if anyone has come across the corruption of textures like this? For reference, the entire background is blue and the leaves should be green.
The source code is very involved, and it’s not mine so I don’t know which parts I would even have to paste. I’m just posting in case someone happens to know any clue of why textures would turn out like this, even though all other OpenGL operations are intact. I believe NSLock (mutex) could be a source of the problem but thats it.