Hawaii’s papaya industry never fully recovered from a virus-driven downturn in the 1990s, and now there is a looming question as to how much of a rebound one of state’s biggest crops can make after the devastating effects of Tropical Storm Iselle.

An estimated 60 percent of statewide papaya production was wiped out by Iselle, which blew through the Puna district of Hawaii island where the industry is concentrated.

It takes only a year for a papaya plant seedling to mature into a fruit-bearing tree. And farmers routinely replant fields every four years. But there is some concern about the immediate supply of seeds and suitable land for replanting that could make for a long, slow rebuilding period.

In addition, most papaya farmers are small, family operations that didn’t have catastrophic crop insurance, which makes it harder for them to remain in the business with severely reduced or no income during a recovery phase.

"Some growers are walking away from their fields and not responding,"said Lorie Farrell, a spokeswoman for Hawaii Farmers and Ranchers United, a farm industry alliance that includes papaya farmers. "The damage is severe."

The organization estimates that lost sales and rebuilding costs related to the storm are at least $56.8 million for papaya farmers based on damage reports from farms and papaya processors.

The total includes $22.7 million to clean up and replant an estimated 520,552 damaged trees covering about 1,600 acres.

Big challenges, however, could limit how much replanting will occur, at least in the next few years.

One major issue is where to replant.

Typically, papaya farmers plant seedlings only on land that hasn’t had papaya trees on it for at least five years because fungal pathogens in the soil left by papaya trees can kill seedlings, according to Russell Nagata, Hawaii County administrator for the University of Hawaii College of Tropical Agriculture and Human Resources.

With so many acres of trees lost, it could be challenging to find enough available and suitable land.

Another constraint is the availability of seeds for the predominant Rainbow papaya that was genetically engineered to withstand the ringspot virus that once threatened to wipe out Hawaii papaya farming.

Nagata said the seeds have a limited shelf life, and production is typically geared in anticipation of normal industry needs.

The Hawaii Papaya Industry Association, the main distributor of seeds, declined to specify how many seeds are in hand but said so far there is no shortage.

Whether farmers can finance replanting is another question. Hawaii Farmers and Ranchers United said only a handful of papaya farmers have any type of crop insurance coverage.

Diane Ley, executive director in Hawaii for the U.S. Department of Agriculture’s Farm Service Agency, said the agency has a "tree assist"program that can provide farmers with money representing a large portion of the cost to replace lost trees, including bulldozing, seeds and fertilizer. A low-interest loan program also is available to farmers who are denied commercial loans.

In some cases, however, small farmers may be hard pressed to take on debt after such a devastating loss. "They may have fewer resources to reinvest in their operations,"Ley said.

At the same time, Ley noted that farmers are typically very resilient and resourceful. "That gives me hope,"she said.

Ken Kamiya, a longtime Oahu papaya farmer, said he has bounced back from 100 percent crop losses three or four times over a 45-year career.

"That’s farming,"he said. "You sit up at night and think how I’m going to pay my mortgage and how I’m going to repay my loans."

Kamiya, whose company Kamiya Gold Inc. grows papaya in Laie and Punaluu, said the challenge for Puna farmers recovering is of similar magnitude to what farmers faced in the 1990s from the ringspot virus epidemic.

"For the farmers there, it’s going to be a rough road for the next couple of years,"he said.

If history is a guide, a rebound may be limited. The ringspot virus had long threatened Hawaii papaya growers, and was a major factor for most of the industry concentrating in Puna in the 1960s, according to the Papaya Industry Association.

The virus took a severe toll on papaya growers in the 1990s, reducing production by about half — from a peak of 80 million pounds in 1984 to 39 million pounds in 1997, according to data from the National Agricultural Statistics Service.

In 1998, scientists released the genetically engineered Rainbow variety that combined traits of two local papaya varieties to protect against the virus.

Since the introduction of Rainbow papaya, production rebounded somewhat, rising to a high of 55 million pounds in 2001 and then sliding back to about 30 million pounds annually over the last decade.

The value of Hawaii papaya sold by farmers last year was just $8.3 million — a 35-year low, according to the Agricultural Statistics Service.

Some observers have questioned the revenue loss estimates from Iselle. The Hawaii Farmers and Ranchers United estimates lost sales for papaya farmers at $32 million over two years, given that papaya trees have two years of commercial productivity before they are cut down and that most trees destroyed in the storm were in their prime.

If $16 million for one year of lost sales represents 60 percent of the industry, that would suggest total industry sales of $27 million annually — about three times what was estimated by the Agricultural Statistics Service.

Farrell said she believes the Agricultural Statistics Service, which has reduced its presence in Hawaii after federal budget cuts, dramatically underestimates industry production and value.

Arepresentative of the Agricultural Statistics Service did not respond to that assessment last week.