Put the summary of the bug you're having here

I expected for the coa-coa bean plant to be connected to the tree

What actually happened was the coa coa plant was not connected to the tree

Steps to Reproduce:
1. plant a jungle sapling and use bone meal to grow it
2. remove all of the coa coa plants that may have grow on it
3. put coa coa beans on the sides of the logs