Everygreen trees have always been used for topping out multi story towers.

[hookedonears]

This is a tradition that's almost always done everywhere for all steel framed multi story commercial towers. The thing that different about what they did at Cars Land is that Cars Land is located in California and in California, evergreens are usually hugged and not cut down. I would bet if you looked closely, the tree is probably a recycled plastic Christmas tree.