There's a large swath of undeveloped land on O'ahu that has drawn the covetous eyes of often-competing interest groups: local farmers, state and city planners, the U.S. Army, Native Hawaiians and environmentalists.

But they are firmly united behind the same laudable goal — keeping the land in agriculture in perpetuity.

The land in question makes up the Galbraith Estate, more than 2,000 acres in Central O'ahu that include Lake Wilson and was once covered with Del Monte pineapples.

The land is now up for sale.

The buyer will determine the area's future: Either for diversified agriculture — clearly its best use — or subdivided by real estate speculators, who would surely attempt to put the land to its most profitable use, high-end homes.

Unfortunately, the second option remains a possibility. The estate's trustee, Bank of Hawaii, is selling the land on behalf of the estate's approximately 700 beneficiaries.

To meet its fiduciary obligations, the bank will seek the best price. This would more likely come from profit-seekers than the public purse.

Nonetheless, there's a compelling public interest in keeping the land in agriculture.

With energy prices driving up the cost of everything imported to Hawai'i, a healthy home-grown agriculture industry is vital to improving our food sustainability.

And the Galbraith property is well-suited to the task: It's high-grade soil, rich and flat; it's close to markets and highways; it has a large irrigation system and plenty of water to support it.

Public control would allow for long-term leases, so farmers could invest in their crops with confidence.

But there are other benefits as well. It's a protective buffer between Schofield Barracks and residential areas on the North Shore.

The Army's Stryker Brigade will traverse part of the land to reach its training grounds in Kahuku. Military exercises and subdivisions simply don't mix.

The land also includes an area of major cultural significance: Kukaniloko, birthing stones located where tradition says generations of O'ahu's royalty were born.

Finally, as anyone driving north on H-2 can plainly see, an agricultural zone between Mililani and the North Shore provides a welcome break from unchecked urban sprawl in Central O'ahu.

The Trust for Public Lands hopes to put together a public/private partnership that would raise money from interested parties, including the state, the city, the Army and the Office of Hawaiian Affairs.

No doubt creative dealmaking will be needed: The economy is weak and the public coffers are thin.

But it's been done before, for Waimea Valley and Pupukea-Paumalu. It can be, and should be, done again.