The proposal between Robbins Lumber Co. of Searsmont and the state to share land at Nicatous Lake in Hancock County is a terrific way for Maine to preserve open space along this beautiful lake. The deal also serves as an important lesson about the state’s long-range plans for its undeveloped places.

Jenness and Jim Robbins bought 22,276 acres on the western side of Nicatous, securing for their mill a long-term supply of top-grade white pine. Managed sustainably, the land will serve the lumber company for generations. But the Robbins family knew it could not afford to keep the shorefront property portion of the purchase and also knew interested developers would be eager to buy it and start putting up pricey vacation homes. Nicatous is along the fringe of the region overseen by the Land Use Regulation Commission, where the commission has directed development.

Eventually, however, the Robbinses decided that development wasn’t what they had in mind, so they did a smart thing: They told the state about their predicament.

The result is a plan that looks like the best of successful Land for Maine’s Future projects. In exchange for $3 million to $5 million, Maine gets the entire parcel under a development easement, with stricter cutting standards near the water; 76 of the lake’s approximately 100 islands, a 243-acre parcel parcel that connects the lake to state-owned Duck Lake parcel. Approximately, $1 million of the money would come from state sources, with the remaining in federal funds.

That’s the good news. The bad news is that the deal shows how ill-prepared the state is to acquire or buy development rights for other valuable spots. The problem is long-standing but can be traced recently to a hopeful proposal by an advisory panel to Gov. Angus King. It concluded that Maine should set aside $45 million, through a bond issue, for land preservation. As a comparison, voters approved a $35 million bond in the mid-1980s for Land for Maine’s Future purchases. The Legislature last session, however, wasn’t thinking that big. It figured $3 million was plenty.

No surprise that $3 million to buy land is sort of like giving your kid $100 and a socket wrench to buy a car — she’s grateful for the money but she’s not going very far. Sappi land is for sale; Bowater’s might be. The state hasn’t the wherewithal to get involved in making those big purchases, but it is an easy bet that once those lands are sold the new owners will look to sell off portions to help pay down their debt. How has Maine positioned itself to take advantage of this?

The answer is that it largely has not. The deal at Nicatous Lake would take about one-third of the total funding for state land purchases at a time when Maine should want to be especially prepared to make targeted buys of unusually important parcels. Clearly, that is going to take money — money that could have been raised through a $45 million bond question.