Texas' grain elevators are monuments to the nation's bountiful harvest.

James Turnbow with I.P.S. Seeds recently gave me a tour of a soybean elevator in Muleshoe.

Whether the elevators hold corn, milo, soybeans, or sunflower seeds, they are basically just big storage tanks.

From that common trait, they can vary in size and amenities.

For instance, an elevator near Main Street in Muleshoe has blowers at the top and bottom that dry the soybeans before they go across the railroad tracks to one of the largest U.S. soybean processing plants.

Soybeans arrive at the plant about 60 miles northwest of Lubbock by railroad car from around the world, not just from Texas fields. Five of the six elevators in Muleshoe feed the machines that turn the protein into a white curd that is later added to hundreds of other products.

The biggest I.P.S. storage facility in town has 18 concrete tanks in two rows, each 15 feet in diameter and 110 feet tall.

Figure on average, about 250 bushels in each foot of tower or about 27,500 bushels of off-white soybeans.

Each tank holds the cargo of about seven railroad cars or 28 big trucks.

Concrete silos are better than wood or metal bins because the thick walls insulate the grain from weather extremes, Turnbow said. This is important on the Plains, where temperatures can fluctuate 30 degrees in less than 24 hours.

"You can leave the grain in a concrete silo for year, and it will look as good as when you put it in," he said.

The name grain "elevators" is derived from the conveyor belt, bucket or auger elevators that lift the grain, beans or seeds to the top to fill the silo.

The tank empties by gravity.

Two men can unload a box car or truck trailer in a matter of minutes.

The contents can be held in the elevators until they are sold, used on-site as seed or livestock feed, or processed, which is the case at Muleshoe.

Some elevators are used only at harvest, but others are constantly filled and emptied as commodities move through the market.

The Texas Department of Agriculture monitors grain storage.

"We are to grain elevators what the FDIC [Federal Deposit Insurance Corp.] is to banks," said Rick Garza, coordinator for the state agriculture department's commodity program, "except we're dealing with grain instead of money."

Garza oversees 217 licensed operators with about 500 elevators. The federal government regulates about 500 other Texas grain elevators, including all of the ones for rice and peanuts.

The number of operating grain elevators peaked around 1984, said Ben Boerner, president of the Texas Grain and Feed Association in Fort Worth.

Since then, the total has dropped from 1,500 to a little less than 500. "The small-town, family-owned elevators are going the way of the independent grocers," Boerner said. "The kids aren't interested in continuing the business, so they're either selling out or shutting the doors." The demand for corn for ethanol, however, might arrest the decline.

Texas grain elevators have been around more than a century, with the first one built during the 1890s at the Port of Galveston.

Many concrete cathedrals of the Plains were built after World War II to store grain owned by the federal government. The national stockpile reduced the volatility of crop prices. After the 1985 farm bill, the government began divesting itself of huge holdings of grains.

Texas farmers had a record harvest in 2007, and grain elevators around the state are bursting at the seams. "It was the best in 50 years for South Texas, and some say the best harvest ever for the Panhandle," Garza said.

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