This grove of approximately 400 pines was planted around 1930, when its location was still within the German province of Pomerania. It is generally believed that some form of human tool or technique was used to make the trees grow this way, but the method and motive are not currently known.
Some believe that the woods was deliberately grown this way to make "Compass Timbers", or trees that are deliberately shaped for the purpose of using those odd shapes in ship building. Long straight timbers were great for planking, but sometimes odd shapes were needed for the internal structure and support of a ship. You can read about it here: Compass Timbers