Time is running out in the race to save a significant agricultural greenbelt — critical to the reinvigoration of the industry and as a buffer against the "paving of paradise."

On O'ahu, the greenbelt has been winnowed primarily to the area north of Mililani, including Kunia and the swath of land between Wahiawa and Waialua.

The Legislature has to seize every opportunity it can to preserve what agricultural resources remain, or they will be whittled away, too.

One such resource is the 2,100-acre parcel known as the George Galbraith Trust lands, formerly in pineapple cultivation through Del Monte Fresh Produce but since 2005 listed on the real-estate market.

With Del Monte's operations shuttered, Bank of Hawaii, serving as trustee, was negotiating a sale last year, but in December announced that the deal fell through. The bank announced its plans to relist the property, which has an estimated value between $30 million and $50 million.

The Legislature saw an opening to save the land, as it should. A couple of options already have been proposed that should get a full hearing, and there are other ideas that could be explored as well.

Sen. Robert Bunda, D-22nd (North Shore, Wahiawa) suggests the creation of a new land use category — "historic agricultural landmark" — with the Galbraith lands as the only such landmark, at least for now. In such a landmark, only active agricultural production would be permitted.

Bunda fears that the current agricultural zoning would enable "gentlemen estates," or homes on large parcels in which agriculture is only a marginal concern. Once such a development takes shape, he said, there could be others, further winnowing the stock of viable agricultural land.

He is seeking a way of saving the acreage without an outright purchase. However, critics are rightly concerned that creating such a landmark effectively downzones this land, leaving the state vulnerable to legal challenges.

There are unexplored routes toward the same end. One is a public-private partnership with a mix of funding sources, the public portion securing an agricultural easement, a permanent encumbrance on the property limiting its use to agriculture.

It's cheaper than outright purchase and should be discussed.

However, making all the arrangements would take time, and the trust might not wait that long.

The bottom line needs to be the preservation of these lands for agriculture. If less costly approaches won't work, the state should commit to the outright purchase of the property, as proposed by state Rep. Marcus Oshiro, D-39th (Wahiawa). Oshiro is seeking private partners who can carry part of the financial burden.

That's not all the Legislature should accomplish this session, of course. Lawmakers need to finally finish the job of creating incentives for agricultural businesses so that the process of designating prime parcels as "important agricultural lands" can move forward.

Carving out the land most suited to agriculture is the only hope for expanded local production of food and energy crops, both key components in the state's mission to create a "sustainable" society.

Achieving that goal is at the end of a long road, but saving the Galbraith land for agriculture would be an important step, and a smart investment for all of us.