Plantware's 'Playgrounds of the Future'?

Plantware’s vision is to turn living trees into a new building material.

"By controlling the shape in which trees grow, Plantware creates products that are made of living trees."

"Plantware has developed, and patented, a set of horticultural techniques to grow soft, flexible and shapeless (un-lignified ) trees. These trees are shaped by placing them on temporary templates (jigs) and induced to harden and thicken – whilst retaining the shape of the template on which they were placed. In effect, this allows the “casting” of living material into shapes that were formally impossible to achieve."

Above, their proposal for the "Kinderforest" playground of the future.