Allotment fire...

Interesting idea about rotting the weeds down and re using them SnooziSuzi, one I might explore a bit more.  Not sure how practical it would be for me as I have about 4 or 5 varieties to contend with including the dreaded mare's tail and I'm sure you should avoid composting certain types of weed?

Yes, that's right; you don't want to put weeds with roots (e.g. nettles) or that can regrow from roots (dock, dandelions) onto your cold heap as they could just end up growing in there, but bagging them up is fine as they rot down completely in an enclosed environment - just make sure that any holes that you put in the bag to let the 'juice' (very smelly) drain off aren't big enough for them to make a dash for freedom and start sprouting out of the bag!