Flagstaff

City on the Colorado Plateau in Arizona, home of Lowell Observatory.

At a glance

Source	Author	Role	In one line
The vanishing groves	Ross Andersen	turning point	Around 1901 A. E. Douglass studied ponderosa pines near his observatory in Flagstaff.

The vanishing groves — Ross Andersen (2013)

Source: Original · Readwise highlight

By 1901 AE Douglass was tiring of Lowell’s eccentricities, especially his obsession with Martian canals — an obsession that eventually led to a falling out between the two men. Douglass was also keen to test his theory of sunspots and trees, and so he began studying tree rings in old stands of ponderosa pine near his observatory in Flagstaff, Arizona.

• Role: turning point
• In the article: Around 1901 A. E. Douglass studied ponderosa pines near his observatory in Flagstaff. In 1904 he found thin growth in the years 1899 and 1902, the “Flagstaff Signature” that founded dendrochronology.
• Why it matters: Flagstaff is the birthplace of tree-ring dating in the essay, the first link between sunspots and tree rings.