Yes, grass seeds can be bad for dogs. Grass seeds can become lodged in a dog’s fur and skin, leading to infection and abscesses. They can also cause painful swelling which can progress to an abscess. In addition, if the seed gets into the ear canal it can cause head shaking and excessive licking of the area. To protect your dog from grass seeds, it is important to keep them away from long grass and check their fur regularly for any signs of infection or irritation.