Redwood National and State Parks in northern California are the embodiment of America’s ongoing challenge to balance the country’s economic interests against preserving its natural wilderness, protecting some forested lands while allowing for resource extraction elsewhere.

When gold was discovered in 1849, hundreds of thousands of people poured into California, and redwoods were logged extensively to meet the demand for lumber and other resources. Today only 4 percent of the old-growth forest and its 1,800-year-old trees remain, primarily along the coast. To stem that ongoing loss, Interior Secretary Stewart Udall successfully pushed to establish Redwood National Park in October 1968.

These Landsat images show logging’s influence around the dark green protected forests. Many of the small pink spots in the lower left corner and across the right side of the 1984 scene are logging sites revealed through Landsat 5’s Thematic Mapper sensor. In the 2016 Landsat 8 image, logging seems to have lessened overall, particularly as areas on the right side of the scene experience regrowth.

Today the majestic trees in Redwood Parks—some soaring as high as 30-story skyscrapers­—are under the protection of the National Park Service (NPS), which celebrated its centennial in August 2016. The NPS’s mandate is to help preserve the future of the trees. Landsat’s continuous monitoring will help ensure it.