In a related note, the book says that a number of Conferate dead were buried in a pit by the Union forces near the Tavern where two older markers apparently set near the end of the 19th century now memorialize the battle. This was an area of some of the heaviest fighting...mostly by CSA Missouri units.
Since the Texas units were primarily in another area of the battle field I don't know if there's a specific burial place for their dead or if they were just covered over and left to the elements. Most of the Union dead were later moved to the National Cemetery in Fayetteville.
Both sides pushed on after the battle and the field was left to nature...and local farmers... until the National Park Service established the present Park in the 1950s.