Crows are smart and difficult to get a clear shot on.
We used to lay in wait just to kill one with a .22 rifle or magnum air rifle, then hang the dead crow upside down from his feet so that his wings will spread open. The other crows will go crazy for awhile then leave.
When that crow decays and falls from the tree, start all over again.
This is what my father taught me and it worked to keep the crows from our vegetable garden when I was growing up.
He made it my job to kill that crow.
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