In the Baghdad night, awakened by the rumble of car bombs and the thump-thump of attack helicopters, Peter Smallwood lies in a sandbagged trailer counting his trees. In his mind's forest, the University of Richmond (search) ecologist zigzags through a dark maze of Appalachian hardwoods until he finds specific specimens, unmarked among thousands.

His favorite tree back home in Virginia is a majestic white oak that sprouted before Thomas Jefferson was president. Somehow it escaped the logger's blade. Now it soars 100 feet into the sky; one slice off its thick, scaly trunk could make a dinner table.

His bedtime ritual may not be as soporific as counting sheep. If anything, it only reminds him of the Johnny Appleseed life he left 6,000 miles behind.

"When I'm in the woods I feel at home," Smallwood says. "And right now, I am far away from any kind of deciduous forest."

Indeed, Smallwood, 43, is one of the more unlikely Americans in embattled Iraq.

He is no warrior. He can't build a power plant, a hospital or a school. He speaks virtually no Arabic.

He has spent decades studying forests and the animals that live in them — chiefly how squirrels' constant reburying of their acorns alters the forest's growth.

Yet he willingly traded security and academic freedom for a yearlong job that is unusual and dangerous even by Baghdad standards: He recruits idle scientists and engineers who staffed Saddam Hussein's secret weapons laboratories and factories, and tries to find them peaceful livelihoods.

The State Department (search) launched the idea last December with an initial $2 million grant. It is seeking $20 million over the next two years to substantially expand the program.

Questions over weapons of mass destruction seem like ancient history in the 20 months since the U.S.-led invasion and the rise of the insurgency. But even harsh critics of the Bush White House acknowledge the former Iraqi dictator once had a large research apparatus, known as the Military Industrial Commission (search), that oversaw development of chemical, biological and radiological weapons. Even if no weapons stockpiles were found, the brains behind the operations remain.

Some were Baathist Party (search) elites and informers. Hundreds more are typical physicists, chemists and engineers from Iraq's once-admired university system. Saddam started stripping their labs and pressing them into military research beginning with the Iran-Iraq war in the 1980s.

Saddam's top weapons advisers now are in custody, including Rihab Rashid Taha, known as "Dr. Germ" for making anthrax weapons, and Huda Salih Mahdi Ammash, a biotech researcher dubbed "Mrs. Anthrax." Taha is the wife of Amer Mohammed Rashid, Saddam's missile expert who was no. 47 on the most-wanted list.

A haggard-looking Ali Hassan al-Majid, better known as "Chemical Ali" for directing poison gas attacks against the Kurdish minority, already has been interrogated in a secret preliminary hearing before a tribunal of judges.

Smallwood's job is to run what amounts to a science dating service, creating matches. The scientists' most eligible suitors? Fledgling environment and energy ministries in a suspicious interim government.

The number of recruits on his payroll has nearly tripled in six months. Among them are the workforce of a "pesticide company" that made sarin nerve gas and biologists who brewed botulism and ricin.

Until he makes a match, Smallwood pays the researchers what he describes as a "living wage" of under $1,000 a month.

The program started slowly last summer. Many scientists were hiding or had been imprisoned by Saddam, while others surrendered when the regime fell and were confined. Some disappeared — perhaps they crossed the border to Iran or joined the anti-Coalition insurgency. Others live in exile.

He also offers access to the new Iraqi International Center for Science and Industry, which operates like a scientific halfway house. Among the perks: Internet access, lab equipment and potential collaborations with Western scientists.

"I've got 116 guys so far," Smallwood says in a telephone interview. "I expect to have many more in the New Year."

Smallwood's program is modeled after one the State Department launched in Russia in 1992. Since then, the International Science and Technology Center in Moscow has funded more than $569 million in grants to more than 50,000 former Soviet weapons scientists at about 700 different institutions.

Now, supporters want to expand it to include machinists and other skilled workers who could fabricate weapons for terrorists.

Critics dismiss the effort as "diplomatic welfare" that has produced no commercial products. But supporters say a few prototype technologies appear close, such as an underground explosives detector and a navigational gyroscope for oil and gas drilling.

Other proposals are more fanciful, such as the tomato that bioweapons scientists in Novosibirsk are engineering to be an edible HIV/AIDS vaccine.

"They found a way to survive without selling their know-how to proliferators," said Jon B. Wolfsthal of the Carnegie Endowment for International Peace In Washington, D.C. "It's not a perfect program. But if it keeps them at home, it's money well spent."

Iraq is much smaller than Russia, but bleaker. And the strategic stakes in its reconstruction are high.

Smallwood's agenda is pretty basic: a desalination plant for fresh water, modern science curricula in Baghdad classrooms and laboratories to assist in the cleanup of war debris and pollution.

Smallwood encourages his recruits to apply their skills beyond science, too. For example, the director of a former missile factory wants to re-employ his old workforce to manufacture household products.

One problem: The factory was looted.

Smallwood is paying the director a monthly stipend to support him while he develops a business plan that calls for $8 million in venture capital for new equipment. "The product is being imported by the hundreds of thousands," said Smallwood, who declined to identify the product to protect the director's business idea. "But it's very complicated. The factory and its workers are still a state-owned company, and the government isn't ready to talk about privatizing its factories."

Most of Iraqi's weapons experts probably won't be so flexible or immediately useful. For one thing, they are scientists, not merchants.

And, their initiative was straitjacketed by Saddam's regime for a generation. The younger researchers, especially, have spent their careers doing only what they were told.

But Wolfsthal and other analysts believe the program is good insurance.

"Compared to the cost of the war, what's a few tens of millions to make sure these guys don't relapse?" Wolfsthal said. "These people won't go directly from being head of the nuclear centrifuge lab to the head of water purification. But when Iraq is rebuilt, it will be using every bit of its technological capability."

That day probably won't come during Smallwood's hitch, which ends next summer.

Like other foreigners, he lives and works inside the Green Zone, a four-square mile downtown fortress encircled by 12-foot high blast walls and wrapped in razor wire. His desk is located in Saddam's former Republican Palace on the west bank of the Tigris River. Its cavernous marble reception halls are inscribed with proclamations in Arabic.

He takes meals in a converted auditorium where in 1979 Saddam infamously read off the names of 75 rivals, who were escorted outside and executed.

Sometimes he eats with soldiers just back from patrolling Baghdad's powder-keg neighborhoods. They are the same age as his Richmond students, some even younger.

"They talk about getting shot at, RPGs (rocket-propelled grenades) and roadside bombs, " he says. "It's a jarring juxtaposition."

Just then, gunfire crackles in the background. Smallwood pauses to determine it's direction, then resumes the conversation.

"Hear that?" he asks. "Everything about Baghdad is surreal."

Smallwood does little personal recruiting. Nor can he visit weapons experts in their homes to make sure they are staying straight. In most cases, it is simply too dangerous for both sides.

He meets regularly with his Iraqi staff inside the Green Zone. Once a week, Smallwood ventures out to visit the program's advisory committee of Iraqi scientists and engineers at other locations in the city.

He straps on body armor and a helmet to ride the few miles each way in an armored Humvee. He is escorted by a dozen troops riding in three or four vehicles commanded by a young officer.

Smallwood was offered the job after serving for a year as an environmental policy fellow on Capitol Hill. He is not married and has no children, an appealing combination for such a post.

"I'm sure the applicant pool would not have been large," he said.

Another rumble interrupts. He scans the Green Zone rooftops. Nothing. Then another rumble.

"Hey, that's real thunder," he marvels. "It's actually starting to rain."

Which again reminds Smallwood of his trees. Their autumn colors would've peaked just before Thanksgiving. Now the damp, cold forest is flecked with muted reds and golds. He'll miss spring, too.

Smallwood is convinced that most Iraqi weapons scientists feel a similar attachment to their desert homeland. He wants them to feel that tug while they wait together for Iraq to rebuild.

"When somebody in a neighboring country offers them ten times the money to go, what will they do?" Smallwood says. "I can't protect them from getting those offers. I only can make it easier for them to say no."