To Pierneef the tree is not simply a natural object, it was a means of expression, thought, and a feeling.To Pierneef the tree was both a psychological projection of man and a symbol of life, forming a link between heaven and earth....The leadwood tree in particular was a symbol of eternity to him. (https://nladesignvisual.wordpress.com/2013/01/18/pierneef-1886-1957/)