Northwest poplar or Carolina poplar

Description:

Family: willow. Species: decidous tree. Height: up to 30 m 99ft. Leaves are triangle to ovate dark green gloss and very tight. Leaf shape: triangular. Margin: notched. Position: alternate. Foliage: yellow. Flowering : April

Habitat:

Olds College Ab. Wetlands , slightly shaded, but also gets decent sunlight throughout the day.

Notes:

Why is there a big scar like this on the tree ? What could it possibly be from? Also the little scar on the tree as well? What would cause or do these things to this poplar?