The Northern Flicker doesn't prefer a tree over another when preparing a nesting site, although it does prefer a tree with a soft or partially decaying heart. (Inner part of the tree)
This Northern Flicker made its nest in a Eastern White Cedar tree, approximately 10 feet up. It had excavated it with its mate, and you can see just below the entrance hole, their is another hole they had started but decided against it. The period of incubation is between 14-16 days. The male incubates them during the night, while the female incubates them during the day.
When the eggs hatch, they remain in the nest for 25-28 days. You can see flickers hopping along the ground looking for and probing the ground for insects, an unusual characteristic in Woodpeckers