The letter J, 30 day challenge

Well! I really don't like this one. It's a jicama, which apparently is a type of turnip. I put far too much black ink pen in this one. This vegetable is actually very pale in colour. Can you spot the mistake (clue: a line going down the right hand side...oops!). Not being allowed to make any corrections, it stays! What  pains me is that this is going to be on top of my blog until I post a new one!