But in the 19th century, when the United States began to industrialize and expand westward, many farms were abandoned by northeasterners who moved to cities in search of factory jobs. Around 1845, Henry David Thoreau described the decline of New England farming: “Now only a dent in the earth marks the site of most of these human dwellings; sometimes the well-dent where a spring oozed, now dry and tearless grass, or covered deep—not to be discovered till late days by accident—with a flat stone under the sod.”
Centuries later, forests have reclaimed much of the land. The images above show the site of an early homestead in the Natchaug State Forest in Eastford, Connecticut. The natural-color photograph was shot during an aerial survey in 2012. The monochromatic light detection and ranging (lidar) image, captured in 2010, shows the same area with greater contrast and reveals features on the ground.