Two narrative episodes in the Hebrew Bible feature a character named Tamar: Judah’s daughter-in-law in Gen 38 and David’s daughter in 2 Sam 13. In this study, I argue that these Tamar figures can be linked to imagery evoked in the Genesis Apocryphon’s reinterpretation of Sarai (1Q20 XIX, 14-16). In the Genesis Apocryphon, Sarai appears to Abram in a dream as a date palm (תמרא) who saves Abram, a cedar, by intertwining her roots with his. Few have connected these Tamar accounts, but those who have identify fertility as the critical thematic link. This essay shows how the Tamar characters in Gen 38 and 2 Sam 13 and Sarai-as-Tamar in Abram’s dream in the Genesis Apocryphon are linked not by fertility but rather by transgressive familial relations. The incestuous motif draws upon the botanical image of the date palm, which is explored in the Genesis Apocryphon’s rendering of Abram and Sarai in Egypt. There, Sarai appears to Abram as a Tamar figure—one whose desirability above ground is apparent to all, but whose roots entwine fortuitously with the roots of others. Through a close reading of the texts, I demonstrate how the image of the date palm evokes the character of a woman in the family who is desirable above ground but strategic and invasive below ground.