Pruning the Tree is the thirteenth puzzle in Virtual Villagers 4.
The requirements to solve: Level 2 Dendrology, Puzzle 1, Puzzle 4 and Puzzle 8.
Drop an adult onto the sick branch of the tree. They will go get cloth to bind the branch.
Drop an adult to the cutting tools and they will cut off the sick branch.
Drop an adult on the soap in the lab to clean the black spots.