The jungle biome is sometimes splitted. There aren't and wont grow trees where these splits, which is very annoying. You can't even place water in this split zone. I've found two splitzones in two different worlds before, and the lenght varies (7-13 blocks) while the width is usally over 500 blocks and very often longer.
One of the most annoying things with this is that jungle trees are splitted too. Those 2x2 (width) trees are suddenly 1x2. It's like nothing can grow within that zone.

What I expected to happen was a normal jungle that's not buggy and no zones where nothing grows.

What actually happened: There was a buggy split in the jungle really close to my house.

Steps to reproduce:
I don't know. Guess it's just a random bug that occurs as the world generates that area for the first time.