I must have read the first 23 pages of ‘Constructive approaches to composition’ in Paul Klee’s Notebooks Volume 2, The Nature of Nature, at least 20 times. The very last line of the section, on page 23 simply states, “Exercise: Imaginary leaves on the basis of the foregoing basic rules.” [All quotes are from: Klee, P., Heinz-Norden, trans. Jürg Spiller, ed.; Notebooks Volume 2 The Nature of Nature London: Lund Humphries. 1973]
In a previous post, I outlined what I thought were the rules. I found I had to focus on a limited number of rules in order to be able to put pencil to paper (to take my point out for a walk, in Klee’s parlance). Klee’s says that the visual expression of a leaf “is defined by stem, veins and leaf tissue,” and that the main line that describes the leaf, i.e., the continuation of the stem through the leaf tissue, is the central vein.
Klee goes on to say that the main line may be divided in equal parts or unequal parts.
Therefore, central vein division is the first rule.
Next, Klee explains that other divisions can be formed by extensions, or branches to the left and right of the central vein (either alternately or bilaterally).
The second rule is branching to the left and right of the central vein at the points where it divides.
Klee adds the following statement: “Note that he line is charged with force especially at the point where it must produce as many branchings as possible, namely at the beginning, close to the stem. In this way reciprocal relations arise between the articulating intervals and the strength or force of the lines (proportional measure and proportionate weight).”
I interpret the above paragraph to mean, the width of the line that makes up the main vein is halved at each division.
Rule 1: central vein divisions – even or uneven spacing between divisions.
Rule 2: at each dividing point, create branching to right or left, either alternate branching or bilateral branching.
Rule 3: the thickest line is at the beginning of the central vein, halving in width with each division.
In my first study, I have 3 divisions of the central vein, the thickest line is from the base to the first division, which is halved between the first and second division at which point it is halved again.
I decided to branch bilaterally at each division, trying to approximate halving of the side-vein lines with each subdivision. In my sketch, I did not use precise measurements and guessed what the limiting line would look like.
Limits of visual discrimination
As I continued the bilateral branching, I quickly reached a limit where my pencil point could not draw finely enough. The bounding surface (or plane) at this limit is what Klee terms a ‘contour’, further on in the section.
I sketched these contours at the limit of the branching.
I used even spacing again, in my second study. However, I used alternate branching. I used a more precise method in this sketch and started with a central vein comprised of a main line with 8 parallel lines, 4 on each side. After the first division, the central vein was halved to 2 lines on each side of the central line, and so on.
I gave the first set of branches the weight of 4 lines, the second set, 2 lines, the third set, one line.
Subdivisions off each branch were treated as if it were the main branch, halving the central line with every division.
In the final division, however I ended with a single main line extension of the branch accompanied by two bilateral branches.
I know I broke my own rules, but I couldn’t find a graceful way to end the branching.
I am not sure how these two studies would have been received by Klee himself had I handed them in as assignments, but I would have really valued his feedback.
I am not done with leaf exercises yet. There are palm leaves, which Klee does address, not to mention more possibilities with linear branching.