WESTVILLE, N.Y. — "Got milk?" is getting to be a difficult question when it comes to organic. While more consumers are willing to pay premium prices for organic milk, supermarkets are having trouble keeping it on the shelves as high feed and fuel prices have crimped supplies.

As organic milk — which federal regulations require be from cows fed organic feed and free from production-boosting synthetic hormones — rose in popularity during the past decade, there haven't always been enough farmers to meet demand.

The shortages have been serious enough that some major supermarket chains recently posted signs advising shoppers of reduced supply. Some relief is expected with the seasonal spring boost in production. But industry watchers say this shortage is more worrisome because of jumps in the price of feed and fuel.