The Island’s lush vegetation can impede construction. Luckily, it’s very easy to remove obstacles from the map. Touch the object you want to get rid of and drag the tool that appears over to it.

If you have enough energy, the object will be removed, granting you either coins, or experience, and, with the bit of a luck, even some precious crystals!
Trees and bushes grow again as in real life, so you will need to remove them from time to time.