Turns out it was (is?) an installation in 2004 by Canadian Landscape Architect/ Urban Designer Claude Cormier.
According to his website "new life was given to a diseased tree slated for removal by decking it's branches with 75,000 retrofitted sky-blue Christmas balls". I LOVE it!
He's done amazing installations throughout Canada, France and the US. Below is a pop art piece called Pergola in Normandy France that is comprised of 90,000 plastic balls arranged like wisteria blooms:
His Lipstick Forest in Montreal:
His Blue Forest in Detroit:
A garden installation Solange in Lyon France, where 16,000 silk flowers were attached to ribbons then wrapped around a cluster of tree trunks in a 100 year old forest.
And last but not least, the incredible Blue Stick Gardens he's done in various locations:
From his website: "we began with an image of the garden’s iconic blue poppy, which was scanned, pixelated, and translated into a collection of long, thin sticks. These were then "planted" to form an abstraction of the traditional Victorian mixed border. Painted blue on three sides and orange on the fourth, the sticks create a chromatic effect that is as surprising as it is simple: a visitor wandering through the labyrinthine installation experiences an ever-shifting set of views and vistas. The sensually engaging experience reinterprets the spirit of colour and movement embodied by the original Reford gardens, injecting it with contemporary visual appeal."