I hope you didnt get the wrong message.. I have literally seen squirrels tearing it up . That being said " I always cut as clean a plug as possible" and fill in holes. And am very adamant about detectorists making a good impression as not to put a negative light on our hobby. Years ago my wife and I were detecting a park in Chicopee , MA. And older gentleman approached us and said " okay kids the party is over " at which time I asked him for an explanation . He explained to me that metal detecting wasnt allowed. I told him there were no signs posted that indicated otherwise. Apparently in the 1970's when metal detecting was picking up popularity , the parks were suffering from the affects of detectorists not filling in the holes.. I went on to explain how I do it , and offered him a challenge . I got a target , cut a plug recovered a quarter . He saw the whole operation as he was watching with great intensity. Then I kindly asked him if he wouldnt mind turning around so I could fill in the hole without him watching. When I was finished , I said " turn around and tell me where I dug a hole " he couldn't . So his response to my wife and I was . " Carry on " . We ended up having some good conversation afterwards and also made a friend that day..