"Explorers, Dendrologists--All Were There'

The bioengineer showed x-ray slides of the human heart and brain tissue, and another of a pale-barked manzanita against a wall of dark conifers. She noted the branching patterns (blood vessels, neurons, tree branches) visible in all of these structures and referred to them as “dendritic.” That’s when I started paying attention. More than twenty years ago while writing a magazine story about the maples of New England, I learned about dendrology, the study of trees. The biologist I was interviewing held her hand upright in front of a line of sugar maples and wiggled her fingers. “A tree is a factory for making sugar,” she said, and went on to tell me about that family of English words rooted in the Greek δένδρον, dendron, meaning “tree.” 

A dendrite is the branching part of a neuron and, in minerals, a “crystalline growth of branching or arborescent form” (OED). To be dendroid or dendritic is to be tree-like in form, like the biologist’s upright hand. From the same root we get the floral names “philodendron” and “rhododendron,” and the science of trees, “dendrology.” James Russell Lowell in a letter said the sonnet as a form is “‘susceptible of a high polish, as the dendrologists say of the woods of certain trees.” Family trees and language trees are dendritic, and Dendron is the name of a town in southeastern Virginia. Nabokov celebrated all things dendrological in “The Ballad of Longwood Glen”: 

“Explorers, dendrologists--all were there;

 And a strange pale girl with gypsy hair.”