SAN ANTONIO - Limestone is missing from the facade, tree roots push up through sidewalks, and windowsills are rotting on the only building generations of Texans have been told never to forget.

"We want people to think about the Alamo again," Rebecca Bridges Dinnin, its director, said in her San Antonio office, sitting beneath the red, white, and green flag of the Texas Revolution.

While Texans are no strangers to tattered public works, with billions of dollars needed for roads, parks, and state buildings, the Alamo's decay is goading business leaders and public officials to act. They're seeking millions to revive the fort, which has been the state's symbolic heart since a bloody 1836 defeat there rallied Texans to wrest independence from Mexico.

On March 12, Texas fired the Daughters of the Republic of Texas, a private organization that has managed the site, after waning gift-shop sales and allegations of mismanagement. State Sen. Jose Menendez, a San Antonio Democrat, wants to ask voters to approve spending as much as $250 million to restore the complex. A new endowment board, which includes billionaire Red McCombs, met this month to consider ways to boost fund-raising for the Lone Star State's most famous monument.

"Almost all Texans look at San Antonio as a second home and that's because of the Alamo," said McCombs, 87, the auto-dealership founder who helped start the Clear Channel Communications radio chain.

During a tour, Richard Bruce Winders, the Alamo's curator, pointed to the eroding foundations of the chapel, the main attraction, as throngs of umbrella-bearing visitors took shelter from the rain. A study released in February by researchers at Texas A&M University revealed that almost three inches of the limestone facade had been eroded by water damage since 1960.

"What happens here, down at the bottom level, is when it rains real hard the rain splashes up and hits here," he said, pointing to areas where the rock had worn away. "It takes years and years for that to happen, but it does happen."

The Texas General Land Office, which is run by Commissioner George P. Bush, the son of former Florida Gov. Jeb Bush, is asking the Legislature for $1.5 million for the Alamo's two-year budget and an additional $5 million for preservation projects, such as replacing rotting beams, upgrading storm drains, caulking windows, and adding wireless Internet service. That's up from a total of $1.5 million during the prior two years.

The request would use $620,000 to pay for temporary storage of former Genesis drummer Phil Collins' collection of Alamo memorabilia and artifacts, which includes Jim Bowie's knife and one of Davy Crockett's rifles. The British musician, who was made an honorary Texan by the Legislature, agreed to donate the collection as long as the Alamo builds a museum to display it, said Dinnin, the Alamo's director.

"Texans need to see some of these things," Dinnin said.

Originally called San Antonio de Valero Mission, the Alamo was built in the 1700s by Spanish missionaries seeking to convert the natives to Catholicism.

It was later turned into a military garrison. In 1836, it became the site of a 13-day siege during an attack by Mexican troops led by General Antonio Lopez de Santa Anna. The defeat inspired soldiers who went on to win victory over Mexico with the battle cry, "Remember the Alamo." Texas joined the U.S. in 1845.

The management of the site was given in 1905 to the Daughters of the Republic, a genealogical society limited to women who can trace their roots to Texas' independence.

The group came under scrutiny as upkeep lapsed. Because of a slide in gift-shop sales, which almost entirely sustained the Alamo for decades, it had a $225,000 deficit in 2011.

That year, the Legislature voted to give control to the Land Office, which oversees oil royalties, education funds and public beaches. The Daughters of the Republic continued to oversee daily management through a contract with the state.

In 2012, Texas Attorney General Greg Abbott, who became governor in January, issued a report criticizing "organizational dysfunction, failures to prioritize historic preservation and internal disagreements" at the site. The Daughters of the Republic's contract was canceled last week.

Ellen McCaffrey, president of the Daughters of the Republic, said the group is being unfairly blamed.

"The state Legislature and the governor and all the officials of the state for decades paid no attention to the Alamo," she said. "They ignored it."

Today a busy street runs through the plaza, where shops hawk trolley rides, T-shirts, and coonskin hats.

"The Alamo over time has become a big letdown for people," said Gary Foreman, an Alamo historian who has been pushing to restore the site to its 1836 battleground image. "Instead of asking 'why are you here' and 'how can we make it more rewarding,' we just say 'what are we gonna sell 'em while they're here.' "