Trees
Forest history

How the world’s forests have changed

Ten thousand years of forest history in a few charts: what farming and the lumber boom took, and why the story today is one of slowing loss and steady regrowth.

The long view

When the last ice age ended about 10,000 years ago, forests covered roughly 6 billion hectares, about 57% of the world’s habitable land. Since then the world has lost about a third of its forest, around 2 billion hectares, mostly to make room for farms and pasture. Half of that loss happened over about 10,000 years. The other half happened in the 20th century alone.[1]

Today forests cover 4.14 billion hectares, about 32% of Earth’s land.[2] They hold roughly 3 trillion trees.[11]

World forest area over timeAbout 6 billion hectares after the last ice age, about 5 billion by 1900, and 4.14 billion hectares in 2025. 34566.05.04.1410,000 years ago5,000 years ago19002025billion hectares
Global forest area, billions of hectares. The time axis is squeezed before 1900 so the last century is visible. About half of all forest loss since the Ice Age happened before 1900 and half in the 20th century. Sources: Our World in Data; FAO FRA 2025.

Turning the corner

Forest loss is slowing. The yearly rate of deforestation has fallen by more than a third since the 1990s, and because forests are also regrowing and being replanted, the net loss has dropped by more than half, from 10.7 million hectares a year in the 1990s to 4.12 million in 2015–2025.[2][3] Many countries in Europe, Asia and North America now gain forest each year.

Deforestation per year, by periodDeforestation fell from 17.6 to 13.6 to 10.9 million hectares per year.0510152017.61990–200013.62000–201510.92015–2025Deforestation (million ha per year)million ha / year
Average forest area cleared per year, in million hectares. After counting forest gained through planting and natural regrowth, net loss fell from 10.7 million ha/yr (1990–2000) to 4.12 million ha/yr (2015–2025). Source: FAO FRA 2025.

What actually causes deforestation? Not mainly logging. A global satellite survey found that almost 90% of deforestation from 2000 to 2018 came from expanding agriculture: cropland and livestock grazing.[4] Logging more often degrades forests, which can grow back when managed well.

Lumber and the American forest

In 1630, forests covered about 1.045 billion acres, almost half of what would become the United States.[5] Over the next three centuries settlers cleared forest for farms, and an industrial lumber boom swept from New England through the Great Lakes, the South and the Pacific Northwest. U.S. lumber production hit about 40.3 billion board feet in 1907 and peaked near 44.5 billion in 1909, a level not matched since.[7]

By 1907 U.S. forest land had fallen to about 759 million acres. After that it stopped falling. Farms moved off poor land and back to forest, fire control improved, and replanting spread. Forest area has stayed close to 760 million acres for more than a century (about 765 million acres in 2017), even as the country grew from 87 to over 300 million people.[5][6]

U.S. forest land1,045 million acres in 1630, 759 million in 1907 and 765 million in 2017. 600700800900100011001,04575976516301700180019072017million acres
Million acres of forest land in the area that became the United States. Forest area has held steady for more than a century even as the population quadrupled. Sources: USDA Forest Service FS-1035 (2014); GTR WO-97 (2019).

The forests are also filling in. The total volume of wood in American forests rose about 58% between 1953 and 2012, because trees are growing faster than they’re harvested or lost.[5]

U.S. growing stock volume615.9 billion cubic feet in 1953 versus 972.4 billion cubic feet in 2012.02505007501000615.91953972.42012Growing stock (billion ft³)billion ft³
The volume of wood in U.S. trees rose about 58% from 1953 to 2012. Source: USDA Forest Service FS-1035.

A conservation timeline (U.S.)

  1. 1872: Nebraska holds the first Arbor Day; more than a million trees are said to have been planted that day.
  2. 1876: Congress creates the office of Special Agent in the Department of Agriculture to study U.S. forests.[8]
  3. 1881: That office grows into the Division of Forestry.[8]
  4. 1891: The Forest Reserve Act lets presidents set aside forest reserves from public lands.[8]
  5. 1905: The reserves move to the new U.S. Forest Service, with Gifford Pinchot as its first Chief.[8]
  6. 1911: The Weeks Act lets the government buy land to protect watersheds, creating national forests in the East.
  7. 1933–1942: The Civilian Conservation Corps plants about 3 billion trees.[9][10]
  8. 1972: The Arbor Day Foundation is founded.
  9. 2021: The REPLANT Act boosts funding to replant national forests after wildfires. More →

Sources

  1. Our World in Data (Hannah Ritchie): The world has lost one-third of its forests, but an end of deforestation is possible. https://ourworldindata.org/world-lost-one-third-forests
  2. FAO: Global Forest Resources Assessment 2025. https://www.fao.org/forest-resources-assessment/past-assessments/fra-2025/en
  3. FAO newsroom (2025): Global deforestation slows, but forests remain under pressure. https://www.fao.org/newsroom/detail/global-deforestation-slows--but-forests-remain-under-pressure--fao-report-shows/en
  4. FAO newsroom (2021): Agricultural expansion drives almost 90 percent of global deforestation (FRA 2020 Remote Sensing Survey). https://www.fao.org/newsroom/detail/cop26-agricultural-expansion-drives-almost-90-percent-of-global-deforestation/en
  5. USDA Forest Service (2014): U.S. Forest Resource Facts and Historical Trends (FS-1035). https://www.fs.usda.gov/sites/default/files/legacy%5Ffiles/media/types/publication/field%5Fpdf/forestfacts-2014aug-fs1035-508complete.pdf
  6. Oswalt et al. (2019): Forest Resources of the United States, 2017 (GTR WO-97). https://research.fs.usda.gov/treesearch/57903
  7. USDA Forest Service: Historical Forestry Statistics of the United States, 1749–1956 (lumber production table: 40,256 million board feet in 1907; 44,510 million in 1909). https://esmis.nal.usda.gov/sites/default/release-files/qb98mf45k/3r074z444/dr26z156v/forestprodstat_Historical_Forestry_Statistics_of_the_United_States__1749-1956.pdf
  8. USDA Forest Service: Our History. https://www.fs.usda.gov/learn/our-history
  9. National Park Service: FDR’s Conservation Legacy (Civilian Conservation Corps). https://www.nps.gov/articles/fdr-s-conservation-legacy.htm
  10. USDA: Celebrating the Civilian Conservation Corps. https://www.usda.gov/about-usda/news/blog/celebrating-civilian-conservation-corps
  11. Crowther et al. (2015), Mapping tree density at a global scale, Nature 525. https://www.nature.com/articles/nature14967