There is nothing more obvious on Turtle Island...

...than "Aesthetic Farm Maintenance."

https://pahistoricpreservation.com/finding-meaning-stone/

In my experience, in the Nonnewaug Cluster, a boulder is used for a carapace:

Allen or "Turtle Rock"in Alabama:

A Boulder and Stacked Stones Variation:

http://wakinguponturtleisland.blogspot.com/2014/05/scuppo-rd-box-turtle-surprise.html

https://wakinguponturtleisland.blogspot.com/2015/12/arguing-with-my-hero.html