Have found that when p;anted on reasonably level ground stumps remain too low to the ground to hit with an axe.

I had started a fir forest near my base for wood to make charcoal but from 12 trees planted, 4 stumps were unable to be chopped. I circled them and tried from all distances and directions but could not hit them. Leaves a visual nuisance at best.

Resorted to moving my woodlot to a fairly steep slope where I could guarantee getting a shot at them.