Between September 29, 1295 and April 1, 1296 Majorcan writer, philosopher, logician and polymath Ramon Llull published Arbor scientiae. This encyclopedia and pioneering work in knowledge representation included sixteen trees of scientific domains following the initial tree called the arbor scientiae.
"An expression of his [Llull's] mystical universalism, this encyclopedic work concentrates on the central image of a tree of science, able to sustain areas of knowledge. Appearing the very beginning of the book, the illustration of the tree of science works as an introduction to his beguiling concept and a sort of arborescent table of contents. This great tree comprises eighteen roots, which relate to nine transcendent principles (not detailed) and nine art principles: difference, concord, contrareity, beginning, middle, end, majority, equality, and minority. The top of the tree is made of sixteen branches, each bearing a fruit and a label, representing the different domains of science, which are then depicted as individual trees in the remaining pages of the work.
"The first set of trees related to profane knowledge. . . .The second group covers the entirety of religious knowledge. . . ." (Lima, Visual Complexity. Mapping Patterns of Information  31-35).
None of Llull's books appear to have been published in print in the fifteenth century. Editions of the Arbor scientiae, with their famous woodcut renditions of Llull's trees of knowledge began to appear early in the sixteenth century, of which an edition printed in Lyon, 1535 was available through Google Books in January 2013.
Dictionary of Scientific Biography VIII (1973) 547-550.