Trunk Traits
If your subject be a tree, observe particularly wherein it differs from those of other species: in the first place, the termination of its foliage, best seen when relieved on the sky, whether pointed or rounded, dropping or springing upward, and so forth; next, mark the character of its trunk and branches, the manner in which the latter shoot off from the parent stem, their direction, curves, and angles. Every kind of tree has its traits of individuality—some kinds assimilate, others differ widely—with careful attention, these peculiarities are easily learned, and so, in a greater or lesser degree, with all other objects.
—Asher B. Durand, “Letters on Landscape Painting,” The Crayon (1855)
Below are two sketches created in 2013.