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i have a little one tried to catch him but couldnt get him in time he went underground , the lttle blighter is eating his way through my mint that have taken the time to nurture and was doing realy well tried a little (Mild) soapy water  hasnt worked any ideas

Not too sure Dialeg, I had lots of them last year, I think they might be some sort of sawfly. d**n nuisance, I squished what I could see though.