I have a rental property where some old boxwood hedges are quite overgrown; they range from 4 1/2 to 5 1/2 feet tall. I’d like to trim them back to 3 1/2 to 4 feet tall; I know they’ll look ugly for a while, but I can put up with that. Will a gas powered hedge trimmer like a Stihl HL94 power through the heavier branches?