More than 130,000 acres of private land had become protected green space in the Lowcountry by the end of 2009, and land trusts were still signing private conservation easements at record-breaking pace, recession or not.

Then the groundswell abruptly stopped.

Lowcountry Open Land Trust saw the number of property owners who signed easements drop from an average 15-20 a year to 10 in 2010. Edisto Island Open Land Trust watched the number of property owners drop from nine in 2009 to none. Other conservation groups saw similar dramatic drop-offs.

"We were all in the same boat. Everybody was very slow. Very slow," said Lewis Hay, Lowcountry trust land protection director.

No, it wasn't the bad economy. The groups stayed busy with property owners who are interested in easements. But most owners hesitated to sign.

The extension of a federal, "enhanced" tax deduction for conservation easement property owners that expired in 2009 was left on the legislative table, caught in the congressional tug-of-war over extending the Bush-era tax cuts.

"When the tax incentives expire, the interest just pretty much stops," said George Kimberly, Edisto trust director.

Congress finally passed the extension earlier this month, making it retroactive to the beginning of the year -- too late to make much difference. The extension runs through 2011; that simultaneously encourages and perturbs land trust groups. They know the interest is there. But the enhanced incentive twice now has been extended for two years. It's still undecided whether it will be made permanent.

"It's an enormous motivation," said Roy Richards, who has put one large tract he owns under conservation easement in the ACE Basin near Green Pond, and is considering putting a second under easement specifically because of the temporary extension.

"I'm pretty sure that this and other tax incentives have got to go away in the new tax regime that will take place. Anybody who's conservation-minded ought to take advantage. It's an opportunity to do the right thing without hurting you too much, if you care about your land and are interested in having that piece of land work its magic on your children and their children," Richards said.

The trusts are nonprofits working with private landowners to set easement restrictions on how those properties can be developed. The effort has been characterized as an important part of the quilt of public and private conservation that has set aside that huge swath of green space around the greater Charleston area.

The tax incentives help make up for a loss of some market value of property put under easement. Some owners also set aside adjoining property for development, and that property becomes more valuable with the conserved open space.

The deduction makes the deal financially attractive for people who have land, but work it, and aren't wealthy enough to give up the option of developing or selling for development.

The enhanced incentive jump-started a run of several years of land easements that made land trusts the most successful private conservation effort in history, conserving more than 35 million acres nationwide, according to the Atlanta Journal-Constitution. The incentive was a boon to property owners; the open land was a boon to the community.

"People have said again and again that they want more green space, that conservation is worthwhile. There's only two ways to get it. One is to buy land, which is god awful expensive, and the other is to put it in easement. We look at it as the ultimate property rights decision," Hay said.

With the incentives in limbo, too many landowners were leery. "We had a lot of people whom we talked to who hesitated, who said, 'I just don't know what's going to happen,' " Hay said.

Staff of both land trusts are encouraged they will get back on pace conserving land in 2011; but are uneasy about how much the effort can continue its record success after that.