Sir; I can't agree with Peter Yarwood's letter about a tax on plastic bags (The Grocer, May 11). Even putting aside some shaky arithmetic (9p is the same as 15c not double), we need to do something about plastic bags now, because our countryside is littered with the bags. We can't wait for some boffins to come up with biodegradeable bags, even if it is ever possible to invent a bag which will decompose, but not so quickly that it dumps all your shopping in the car park. The simple solution is the bag for life scheme which some retailers operate. The sooner the tax is imposed the better. Peter Jones Manchester {{LETTERS }}