The conflict has been "distracting and negative," the traditionally tightlipped group said in a statement announcing the expulsions.
Erin Bowman and Dianne MacDiarmid had spoken out this summer against the group, saying they believed it lacked the ability to ensure the financial stability of the 18th-century mission. The organization has never operated the Alamo in the red, but the women say a stronger financial plan is still needed.
Bowman and MacDiarmid declined to immediately comment on their expulsions. They have launched a nonprofit organization, the Alamo Endowment, to raise money for preservation and educational programs.
"We're trying to decide where to go from here," Bowman said.
More than 2.5 million people a year visit the Alamo, which charges no admission. The Alamo receives no state funding, and gift-shop sales have provided 90 percent of the site's $5.5 million operating budget. The Alamo also receives donations.
The Daughters voted to expel Bowman and MacDiarmid on Nov. 20, the same day the 26-member board heard from the pair at separate, one-hour closed meetings in Austin. Until recently, the only expulsion was one member accused of embezzlement about 10 years ago.
Bowman and MacDiarmid want the Alamo run more like a modern museum, with national accreditation and a business plan that includes foundation funding, licensing and marketing. Because the Daughters are custodians of the Alamo, it was unclear whether the ousted duo could get a permit to perform any work on the Alamo grounds.
Stan Graves, director of the Texas Historical Commission's archaeological program, said the two could raise funds for the Alamo even without the Daughters providing their blessing for a permit.