This article appeared in the Summer 1997 issue of New Mexico Resources.

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When eastern New Mexico rancher Sharon Davis first heard about cloud seeding, she thought "there goes Lizzie in The Rainmaker," referring to a play in which a con man travels to a drought-stricken town and promises to make it rain for $100.

Like the Curry family in the fictional story, Davis, who grows wheat and runs a cow-calf operation with her husband near Portales, was skeptical at first.

"But after listening to experts explain the process and doing some research, I have no doubts that it works," she says.

Like Davis, other farmers and ranchers in Roosevelt, Quay, and Curry counties may not be able to control the weather, but they're hoping that scientists can give Mother Nature a nudge by planting seeds of rain.

"The type of cloud seeding we're trying is rainfall enhancement," says Floyd McAlister, Roosevelt County agent with NMSU's Cooperative Extension Service. "Silver iodide crystals -- the seeds -- are applied at the proper time and place to encourage precipitation from clouds containing the right moisture, height, and density. We're tagging along with Texas' High Plains Underground Water District cloud-seeding program, which includes 15 Texas counties along the eastern New Mexico border."

The three New Mexico counties that joined the group formed the Llano Estacado Weather Modification program, and raised more than $230,000 to sign up 3 million acres of land.

Before seeding, meteorologists monitor the weather daily for cloud formation. When conditions are ideal, an airplane flies into the area and releases flares of silver iodide into the clouds. Silver iodide particles gradually rise into the clouds to meet cool moisture, forming ice crystals that turn into raindrops before hitting the ground.

"There are two reasons we're in this cloud-seeding program," says Scotty Savage, a water conservationist with the Natural Resource Conservation Service in Roosevelt County. "One is our survival. We cannot survive without water. Another reason is economics. More water is going to be an economic boost to every person in this area."

Eastern New Mexico is faced with a long-term problem, she says. "We're running out of water."

Depleting the Ogallala Aquifer, a water source for Roosevelt County, is a major concern, Savage says. "When the Ogallala is gone, we're not going to have any water. Right now we're losing water -- a 2- to 4-foot drop each year. In 10 to 20 years, it's going to be gone."

The county is considering pumping water out of Ute Lake near Logan, she says. If this happens, the cost for 1,000 gallons of water will increase from 95 cents to as much as $8 for Roosevelt County customers.

Between 1984 and 1988, nearly 4 additional inches of natural rain fell annually in Roosevelt County, Savage says. During that period, the water table stabilized and water levels rose in many wells.

Savage believes that cloud seeding may be part of the solution.

The notion of cloud seeding is not new. It took shape a half century ago when Vincent Schaefer, a scientist at the General Electric Research Laboratories in Schenectady, New York, tried to get artificial clouds to produce precipitation in a modified freezer. When he placed a chunk of dry ice in the freezer, ice crystals immediately formed. The chemical used, silver iodide, turned out to be almost like ice in molecular structure.

The idea of artificially starting rainfall and suppressing hail inspired further research on weather modification.

"New Mexico had quite a few cloud-seeding projects for about 20 years," says Conrad Keyes, retired NMSU civil engineering department head. "At NMSU, we experimented with snowfall enhancement from Cuba to Santa Fe for four winters, trying to increase snowpack by at least 6 inches per year. We increased the snowfall 40 percent of the time by randomly seeding 50 percent of the storms.

By the late 1970s, enthusiasm for cloud seeding was diminishing, along with state and federal funds. Few researchers could agree on whether cloud seeding was scientifically valid.

Weather experts continued to study the concept, but not without criticism. Some people felt natural processes like rainfall shouldn't be interfered with, and others worried that cloud seeding in one area was "stealing" water from nearby regions.

"Lawsuits were filed from time to time, but none of the cases ever made it to court," Keyes says. "Most of them were associated with floods where airplanes were used to seed clouds."

A lawsuit was filed against NMSU, accusing the university of using airplanes and flares in the early 1970s, he says. But ground-based generators were being used for the experiments, and the case was dismissed.

"Some people say if cloud seeding didn't work then, why should it work now," McAlister says. "But the technology has changed tremendously. It's far more effective than what was used back then, and it has changed even in the last five years."

Today, with radar and computers aboard the aircraft to collect and analyze data, "it's a piece of cake," Keyes says.

"In a semiarid area, cloud seeding is important because an increase in precipitation at the right time could increase productivity," McAlister says. "Anytime you can improve productivity, you increase dollar return."

More rain simply means more money for farmers and ranchers, Davis says. The cost of cloud seeding is cheap -- 8 cents an acre.

"One agricultural economist figured out for every dollar spent, a producer will reap $700 in benefits," says Davis, who also runs a furniture store with her brother. "It's just phenomenal what rain means and how it affects the entire community. As a retail merchant, I've seen the difference. A rancher is not going to buy that sofa when he doesn't have a good year."

Atmospheric scientists with Weather Modification Inc. of Fargo, N.D., say properly designed cloud-seeding programs can dissipate super-cooled fog, increase seasonal rain or snow, and decrease seasonal hail damage. They cite 50 years of research and operations in 43 countries.

Different types of clouds are seeded, depending on the project's goal, says Terry Krauss, chief scientist for Weather Modification Inc. Large thunderstorm clouds that are likely to produce hail are seeded to lessen damage, while smaller clouds that are likely to grow are seeded to increase rainfall.

"Natural clouds are not very efficient on their own," Krauss says. "We can make them more efficient and enhance rainfall, but we cannot guarantee an amount of rain because the whole depends on clouds."

This shouldn't seem strange to the agricultural community, he says. After planting wheat seed, farmers have no guarantee of their yield, either.

"We know cloud seeding works from weather modification programs that have been going on in Texas for 25 years in Big Spring and six years in San Angelo," McAlister says. "Rainfall increased there 20 to 30 percent above normal."

Testimonials from pilots who take aerial photographs are what impressed Savage. "For a while, these pilots were wondering why a certain section of the High Plains was greener. It turned out to be the cloud-seeding area," she says.

Seeded clouds also have produced longer rains, experts say. In addition, they attract unseeded clouds to cause rain over larger areas.

However, weather scientists agree cloud seeding should not be considered a drought-buster. Clouds must be present to seed.

"Ranchers can always use more rain, and dryland farmers are always one rain away from making a crop," Savage says. "I want them to use the best technology available for water management, which includes irrigation and cloud seeding."

Farmers and ranchers in eastern New Mexico are waiting to see what kind of harvest they will glean from seeds planted high above the ground this summer.

Cloud-seeding advocates also hope to gather enough proof to water down criticisms and draw up support from other New Mexico counties in the future.