This morning we discovered this odd area in a flower bed. The area is
below a large wax leaf ligustrum. Neither of us has seen anything
like it before.

The area looks somewhat like it has been dusted with chalk, but the
white dash looking objects are growing out of the ground. They look
like exposed roots, or some kind of sprouts.

http://www.factsfacts.com/what_is_this_white_growth.htm

jim