Flooding and drought hit Hawaii taro farmers hard last year, reducing estimated production of the crop to its lowest level in at least 20 years.

Just 3.4 million pounds of taro was brought to market statewide in 2012, according to a report from the U.S. Department of Agriculture’s National Agricultural Statistics Service based on a survey of farms in November.

Production was down 17 percent from 4.1 million pounds the year before, which was roughly the average annual production level during the five years from 2007 to 2011.

The report said torrential rain washed out entire crops last March, and then drought conditions persisted later in the year to cause additional problems. Some taro growers also reported that high water prices were a problem.

Not all taro farms were hurt by water problems. At Kapahu Living Farm on Maui, the main supply of water comes from streams that did not run dry last year as they have done in some years. "It was a good year," said Scott Crawford, executive director of the nonprofit group Kipa­hulu Ohana, which operates the roughly 2-acre farm within Hale­akala National Park. "We didn’t have any major negative impacts."

Hawaii was home to 105 taro farms covering 400 acres last year, the statistics service said. The value of last year’s crop was $2.3 million based on an average price of 67 cents per pound. The industry crop value was down from $2.8 million in 2011 solely from the production drop, as the average price was unchanged.

Peak production over the past two decades was 7 million pounds in 2000 — twice the amount produced last year. There was only one other year in that period when production was below 4 million pounds. That occurred in 2010 when 3.9 million pounds of taro was produced.