Cromm, the sod would take care of much of the deterieration from rainfall.
I see what you mean Rod, but why would you have a round butt when you wouldn't shoot from all sides, but only the sides between the two butts? As for labor, sure, they were used to building earthworks, and it was an agrarian society used to working the soil. Labor though is labor, and not cheap. Most of the mound seems wasted, aside from the small area the targets were placed at.
Is there any documentation about why the butts were round mounds of eath? Or is it just speculation?
Not meaning to be a pain, but I am very curious about why these things were round and not just straight berms. Cultural bias? Ancient tradition that predates the long bow? Some sort of architectural reason carried on into the Medieval period? Aesthetics? Engineering reasons?
Dane