I am sorry for this delayed reply to your gardening question. The spring rush has brought a deluge of questions and we are working hard to catch up!
The acorns won't harm the flower beds and in fact act much like a mulch and will decompose in time. However, many of them will sprout and become little "weed trees" that you'll need to remove or if they are in a lawn simply mow over.
Thanks for the question. Best wishes for a wonderful gardening season. Please stop in again soon!
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