Editor's note: The Star is publishing a weeklong series explaining the 10 propositions - nine state and one city - on this year's general election ballot.

PHOENIX - Seven times now, voters have rejected ballot measures to give the state the power to trade away public lands.

Sen. John Nelson, R-Litchfield Park, said he thinks the eighth time is a charm, if for no other reason than this plan is different from the last seven.

Nelson believes lawmakers have addressed all the concerns that sent the others down to defeat.

And that could be, as Proposition 119 has no organized opposition - and has the active support of several environmental groups that campaigned to kill the earlier versions.

At the heart of the issue is that when Arizona became a state, the federal government gave it close to 11 million of acres of land to be held in trust. The proceeds from the sale or lease of the property, or from selling timber or mineral rights, is largely earmarked for public schools. About 9.3 million acres remain.

Under the Arizona Constitution, the lands can be sold only to the highest bidder.

Proposition 119 would create an exception for land swaps.

The need is to preserve open space around military bases, Nelson said.

The change would give the state flexibility to make deals with developers who own large tracts of land around the bases. The developers would get other parcels of state-owned land elsewhere on which they could plan communities. And the state would be able to preclude the kind of high-density residential development near bases that leads the military to move out.

There have been many prior versions. Most were defeated amid concerns by conservation groups that savvy developers would find a way to take advantage of such a system, acquiring choice parcels of land, perhaps environmentally sensitive locations, without public oversight.

Sandy Bahr, director of the Grand Canyon Chapter of the Sierra Club, said voters should be skeptical of land swaps.

"There are lots of examples of how the public has been ripped off," she said, as other levels of government, not subject to the constitutional restrictions, have traded away choice pieces of property for something worth far less.

But Bahr said this measure is different.

"Voters have the last say on these land exchanges," she said. "This isn't open-ended, broad authority for the State Land Department to go out and do a deal."

Bahr said that if the state comes up with a proposal, there will have to be public hearings, appraisals and an analysis of the costs and benefits.

Then the plan would go to the Legislature. And if lawmakers approve, the voters will get the last word.

What also brought the environmental groups on board is the belief that while the land exchanges are focused on preserving space around military bases, there could be conservation benefits.

"Some examples could be state lands down around the San Pedro (River) and Fort Huachuca," Bahr said.

"That alone is enough to vote 'yes' on this because the San Pedro is a critically important river from a conservation perspective," she explained. "And Fort Huachuca is essential to the economy of the Sierra Vista area."

Bahr's organization supported a similar version two years ago, which came within 10,000 votes of being approved out of about 1.6 million votes cast.

And that was without any sort of campaign.

Nelson said supporters won't make that mistake again. There will be "more collaboration between the environmental community and those of us on the military side" to ensure there are funds to get out the message, he said.

On StarNet: A breakdown of Tucson-area races, voter resources and links to political news coverage can be found at azstarnet.com/elections

Story schedule

• Today: Propositions 119 and 118.

• Tuesday, Sept. 25: Proposition 120: Declaring state sovereignty over most federal lands in Arizona.

• Wednesday, Sept. 26: Proposition 116 - Reducing the property-tax rate for businesses; and Proposition 117 - Eliminating the practice of all property having two different assessed values for taxes.

• Thursday, Sept. 27: Proposition 114 - Limiting the right to sue for damages if someone is injured while committing a crime.

• Friday, Sept. 28: Proposition 115 - Giving the governor more power in the selection of judges.

• Saturday, Sept. 29: Proposition 121 - Creating a single primary election for all candidates.

• Sunday, Sept. 30: Proposition 204 - Making the existing 1-cent sales tax surcharge permanent; and Proposition 409 - $100 million city bond issue.