While producers in the rest of the nation have seen their crops withered by drought, Idaho potato growers survived a second straight water-short year by producing their fourth largest crop ever.

The government reported that 1988 potato production should total 9.95 billion pounds, down just a fraction of a percentage point from the 1987 harvest. Industry experts said the quality of the crop remained high despite early termination of irrigation in many areas.With the summer drought driving national production down 10 percent, the strong harvest prospects in Idaho gave the state's producers a good chance to cash in on a rising market. Prices for 10-pound mesh bags non-size A, were running around $10 this week, up about $4 from a year ago.

"Idaho's definitely in the driver's seat as far as the availability of potatoes, and not just the availability of potatoes but the availability of quality potatoes as well," University of Idaho agriculture economist Paul Patterson said.

The Agriculture Department said other major potato producing states like North Dakota and Minnesota lost a fifth to a third of their crops to drought this year.

As a result, spokesman Tom Cooper said, Idaho will produce 32 percent of the nation's fall potatoes this year compared to 29 percent in 1987.

The strong 1988 production estimate for Idaho puts three of the top four harvests in the last four years. The record harvest in Idaho was in 1985 when 10.25 billion pounds were produced only to fall victim to an early frost. The second largest crop was just over 10 billion pounds in 1978. The third largest was just last year.

But while Idaho production was effectively maintained, it came from the largest acreage in a decade. Statewide yield was down 900 pounds from a year ago to 28,700 pounds, but that decline was in the eastern and central parts of the state where irrigation supplies ran out very early in the season.

Production outside the 10 southwestern counties was put at 9.21 billion pounds, down about a half percentage point from last year, and yields were off 1,000 pounds from 1987 to 28,000 pounds per acre.

But half that decline was picked up in the southwestern part of the state where growers, benefiting from a slightly longer irrigation season, saw production rise nearly 3 percent to 738 million pounds. Average yields rose 1,000 pounds an acre to 41,000 pounds.