From the healthiest salad to the heartiest burger, American dining has been plunged into crisis: the US is suffering its worst lettuce shortage for a generation. Spot market prices for iceberg lettuce, by far the most popular variety, have soared to 15-year highs as traders from Boston to San Diego scramble to get their hands on the precious vegetables.
Even the largest bulk buyers, like supermarkets and fast-food chains, have been forced to pay prices that few can believe. A crate of 24 heads that would normally cost just $10 is now changing hands for over $50.
Many restaurants and burger chains have adopted sudden menu changes in a bid to avoid passing on the price hikes to customers.
The cause of the sudden lettuce famine has been a crop-shredding cold snap in California, the state which provides around 99 per cent of America's lettuce during the winter months. The problem has been made much worse because low lettuce prices over the past few years have convinced many Californian farmers to concentrate on growing more profitable vegetables.