"In 1904 a young American named Andrew Ellicott Douglass started to collect tree specimens. He was not seeking a pastime to fill his hours of leisure; his motivation was purely professional. Yet he was not employed by any forestry department or timber company, and he was neither a gardener not a botanist. For decades he continued to amass chunks of wood, all because of a lingering suspicion that a tree’s bark was shielding more than sap and cellulose. He was not interested in termites, or fungal parasites, or extracting new medicine from plants. Douglass was an astronomer, and he was searching for evidence of sunspots."
- A.R.T. Jonkers