Sir, - Your correspondent in Finland (July 28th) makes a good point. Litter in Ireland is a national disgrace. Although I live here four months of every year, and have done so since the 1960s, my "home base" is in Arizona, a state of roughly the same population as Ireland.Arizona also has its share of "litter louts", but we have found a fair solution which does much to improve the landscape. It is called the "Adopt a Highway" programme. Any person, organisation, or business may adopt a onemile stretch of road, whether inter-state highway or rural road. Their duty is to clear the visible margins once yearly. (I suspect they do so more often.) After picking up and bagging trash, they report to the local rubbish pick-up company, who take it away.The reward is a small, green roadside sign reading "Adopt-aHighway: (name of business, etc, sponsor). I particularly enjoy a sign reading "God saw you toss that." Many private individuals have joined this programme. It works. - Yours, etc.,Anne Conlin,Kilgarvan House,Coolbawn,Nenagh,Co Tipperary.