"But when I called Beuys with this proposal, I immediately heard hesitation in his voice. He called back two days later. He was a gentle, courteous man. 'A fountain is beautiful', he said, 'but I want to plant seven thousand oaks'."
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"In addition to each oak, a stela of basalt would be placed in the ground - not processed but in the natural form in which basalt is usually broken up in the quarry. That was simple. Beuys said that he considered such an oak with a stone along the edge of the street (as there are always trees) as a sculpture, a sort of tree monument."
Rudy Fuchs on Bueys' sculpture at Documenta 7 in Kassel, Germany in Bomen en mensen , De Groene Amsterdammer, 9-9-2015