An aerial power saw will be suspended from a helicopter to trim trees along three high-voltage electric lines in Michigan’s Upper Peninsula this week. The work is scheduled to begin today and continue through the week on 138,000-volt lines in Baraga, Houghton, Ontonagon and Gogebic counties and Vilas County in Wisconsin. An aerial power saw with rotary blades will be suspended from a helicopter on a 90-foot vertical boom. Aerial Solutions was contracted to do the work by the American Transmission Company (ATC), which owns the lines.