Although Hawai'i's farm sector remains relatively small compared with the $10 billion tourism trade, agriculture continues to play a role in diversifying the state economy, preserving greenbelt lands and reducing the Islands' dependence on imported food.

However, urban development continues to encroach on agriculture. Between 1997 and 2002, the amount of land farmed in Hawai'i dropped 10 percent as sugar cane acres were fallowed or were developed for nonagriculture use. Nationally, farmland acreage fell nearly 2 percent, according to an agriculture census released last year.

Just how far House Bill 1640 will go toward protecting agricultural land is unknown. The bill places no moratorium preventing the reclassification of agricultural land during the identification process, doesn't specify what incentives will be provided to keep land classified agricultural, or ban the reclassification of important agricultural land to another designation at some future date.

Still, "This is landmark legislation," said Dean Okimoto, president of the Hawai'i Farm Bureau and owner of Nalo Farms in Waimanalo. "It's been 27 years in coming and finally we start. The bill is in no ways perfect. It's far from perfect; there's a lot of work to be done.

"But at least we start the process."

Under the new law, the four counties will set about the process of identifying important agricultural lands, which ultimately will need approval from the state Land Use Commission. Additionally, private landowners can voluntarily seek such designation from the state. However, none of the designations will become effective until after the state creates incentives, which isn't expected to occur before mid-2007.

Lingle signed the bill in her state Capitol offices surrounded by local produce including sugar cane, corn, tomatoes, onions, bananas, and a variety of plants and flowers. Agriculture remains an important sector for Hawai'i's economy because it helps keep the state self-sufficient, provides an attractive backdrop for the visitor industry and gives residents the option of living a rural, agricultural lifestyle, she said.

"Each one of those are reasons why we feel so strongly about agriculture," she said. "When you live in a city and your major involvement with agriculture is going to the produce section of the supermarket, you can start to lose perspective about steps that are going to be needed to be taken over the long term to make certain we always have the crops that we need and that food is there for us.

"Agriculture in our state is not what it used to be, we all know that."

Among the recent controversies involving the development of ag lands has been the proliferation of residential projects on land zoned for agriculture. There are at least six agricultural subdivisions on Maui and Kaua'i that are in the planning or sales stages, which has highlighted the debate over what is acceptable land use and whether counties are properly allowing homes on farmland.

Identifying productive agricultural land from less productive land ultimately could aid in identifying which lands can be developed or classified for other uses, said Dean Uchida, executive director of the Land Use Research Foundation, an advocacy group for large land owners and developers.

"I think the development part is ultimately involved, but it's a couple of steps out," he said. "The challenge is going to be how do you create incentives for people to invest in agriculture development.

"That's the next significant challenge."