Today at the allotment one of my fellow allotmenteers showed me some of his sweetcorn plants with some strange damage to the lower leaves. They looked liked they had thin strips scored along the length so much so you could see through them. I thought of slugs or snails but they would eat all the leaf and anyway he had put slug pellets down (I have also never had problems with slugs eating sweetcorn leaves)
Has anyone any ideas.