Answer: How frustrating to watch your baby corn plucked up by crows! It's not a good idea to use petroleum products like the ones you've mentioned in the garden, and mothballs may inhibit the growth of the seedlings, but you can string clear monofilament fish line 6-8" above each row, and a couple down either side of the plot to keep the crows from landing in the patch. They'll encounter the line when they try to land, and get confused by the unseen obstruction. Keep an eye on them, though - they're smart creatures, and may try to find another way into the plot before the corn is too large to be attractive to them. Hope this helps!
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