For many years the name Quercus texana was erroneously used for Q . buckleyi (L. J. Dorr and K. C. Nixon 1985). A few authors have also used the name for Q . gravesii .

Quercus nuttallii E. J. Palmer var. cachensis E. J. Palmer was described as a small-fruited form (nuts 16-18 × 12-16 mm) from specimens collected in east-central Arkansas (E. J. Palmer 1937). Noting the similarity between Q . nuttallii var. cachensis and Q . palustris , Palmer discounted the possibility of the former being of hybrid origin because (1) he had not observed Q . palustris in the type locality, and (2) the leaves and buds of the former were essentially the same as in Q . nuttallii var. nuttallii .

C. H. Muller (1942), on the other hand, argued that Quercus nuttallii was nothing more than a form [forma nuttallii (E. J. Palmer) C. H. Muller] of Q . palustris . This is a puzzling conclusion because it was based largely on the premise that Q . nuttallii occurred "...with the parent species throughout a large part of the latter's southern range (Mississippi to eastern Texas and southeastern Missouri)." The range of Q . palustris does not extend into Mississippi or eastern Texas, although its range does overlap that of Q . texana in eastern Arkansas and southeastern Missouri. E. J. Palmer (1948) and D. M. Hunt (1989) have suggested hybridization with Q . shumardii and Q . nigra , respectively. See L. J. Dorr and K. C. Nixon (1985) for an explanation of the nomenclatural confusion regarding this taxon.