When ever I Check the Collision with World option, It spawns significantly less foliage. I have to Increase the Seed Density and Steps to the Point where my Computer (i7-6700, 8Gb RAM) struggles. It is also a very tiny area.
On top of that, it also seems to not resolve the problem. The empty patch of land is still beside the “treetrunk”.
I keep trying to solve the problem myself and hope that there is an easy solution.
Thank you for your help so far.