Montreal and Hydro-Québec are experimenting with y-shaped metal frames to protect power lines from growing saplings.

The pilot project is testing whether trees will grow along metal frames, shown here. (Salimah Shivji/CBC)About 60 young trees in Montreal's Rosemont district have been fitted with the contraptions as part of a three-year pilot project to improve the city's power grid during extreme weather conditions.

The city of Montreal is working with Quebec's power utility and a provincial forest research group to test whether young trees will grow around the metal frame, avoiding overlying hydro lines.

Nearly half of all power outages in Quebec are caused by tree branches interfering with hydro lines, said Daniel Desjardins, the head of Montreal's tree department.

Hydro workers currently trim tree branches once they grow too close to power lines, a time-consuming and inefficient solution, said Desjardins, because "if you prune, you have to prune again, and again, and again, because where you prune you're gonna [see] more branches."

If the trees respond to the metal frames, Montreal will consider introducing the technique to other parts of the city, Desjardins said.