Try this:

Find a decent mast tree area.
Bring your scoped .22 or .17hmr and a camp chair.
Pick a good spot then glass or wait for treetop movement.
Limit your movements.
Headshots only please.
Drop a squirrel, take note of where he is.
Stay in your chair, another will be along momentarily.
Limit out, go collect your bushytails at the bases of each tree.

Works best when mast is still attached to the trees.

True story: A buddy and I limited out, 12 each in two hours doing just this.