smooth+leaves

You have found Balsam Poplar woo hoo yipee

Leaves: Alternate, simple, oval or heart-shaped, sharp-pointed, rounded teeth, 7.5-15.0cms long, shiny dark green above and pale green beneath/ Flowers: Inconspicuous, small in dense catkins, pistillate and staminate flowers on different trees. Developed before the leaves expand in the spring.

For more info go to Wikipedia.org thanks for reading.