Better solution would be to use image recognition - like kooaba. Take a picture of the burlap seam with your phone, then recognise it to list the contents. Burlap actually has an irregular pattern, so it is recognisable (like a finger print), but your image recognition would need to be trained for that kind of recognition -- and I've only ever used shape-based recognition, so I don't know how close we are.
It is more common to SEW your tags into the burlap seam. Are you sewing your bags shut?