This isUntitled(SF.045c Potato Print - Branches, Purple and Blue), circa 1951 to '52. It's a stamped ink-on-Japanese-paper print, about 14 inches tall and 10 inches wide, oriented vertically.
To create this work, Asawa took an ordinary potato about the size of the palm of her hand, sliced it in half to give her a flat surface. Into the surface of this flat potato, she incised a tree-like form with a center trunk topped by a loop. And then on either side of the branch are four branches with loops at the end as well, alternating left and right. The potato would have been dipped in purple or blue ink and Asawa pressed it to the paper in a repeated pattern across the page, allowing the ink to deplete over the course of the row, resulting in layers of transparent blue and purple ink.
Asawa oriented the potato stamp vertically and pressed it onto the paper eight times per row in the same vertical orientation, overlapping the stamps occasionally. Each of the three rows moves off the edge of the sheet to the left and the right, giving the sense that infinite repetition was possible in this print.
She chose to print this work on Japanese paper. It's a very thin paper that also responded to the liquid of the ink and there's a rippling along the surface as well.
Asawa did not re-ink the potato as she moved across the row, so the ink would become lighter and lighter as she moved across. And in some cases, only the outline of the tree form was left. This really gives you a play of positive and negative space and transparency, which reflects her practice in other works of art.