A poplar tree of northern North America (Populus balsamifera) having ovate leaves and large buds coated with a sticky, fragrant resin. Also called hackmatack, tacamahac. North American poplar (Populus balsamifera), native from Labrador to Alaska and across the extreme northern U.S. Often cultivated as a shade tree, it has buds thickly coated with an aromatic resin that is used to make cough syrups. It grows best in northwestern Canada