The difference between woods and forests comes down to canopy cover and tree density. While forests are known for thicker canopy cover (the amount of land covered by the tops of trees), woods usually have a more open canopy and sparser tree density, keeping the soil drier and unshaded. Although both refer to distinct ecosystems covered in trees and home to a wide range of wildlife, woodlands are often referred to as the ecosystems in between dense forest and open land.
The distinction between woods and forests actually goes back to medieval times, specifically when a “forest” referred to a plot of land big enough to preserve large game for royal hunting parties. Today, the UN Food and Agricultural Organization (FAO) and the U.S. National Vegetation Classification system both offer similar perspectives on how to differentiate between the two.
Which Is Bigger, a Wood or a Forest?
Ecologically speaking, both forests and woods have trees higher than 5 meters (16 feet) and can span the same amount of land. A forest, however, has a canopy cover of over 60%, meaning it may be denser than a wood while still maintaining the same land size.
What Is a Forest?
According to the FAO, a forest covers more than 0.5 hectares (about 1.24 acres) of land with trees higher than 5 meters (just over 16 feet) and a canopy cover of over 10%. Forests also include areas with younger trees expected to reach a canopy cover of at least 10% and tree height of at least 5 meters and do not include land predominantly used for agriculture. Forests provide habitats for nearly 5,000 amphibian species (or 80% of all known species), 7,500 bird species (75% of all birds), and over 3,700 mammals (68% of all mammal species).
The U.S. National Vegetation Classification system considers forests to be vegetation dominated by trees at least 6 meters (19 feet) tall producing a majority of closed canopy, usually between 60% and 100% cover. However, they suggest that forests that have temporarily lost their cover due to a major disturbance like disease or windthrow are still considered forests.
The forest biome is made up of three general types: Temperate forests have temperatures that vary throughout the year, making up four distinct seasons; tropical forests are found closer to the equator with warmer, more humid climates; and boreal forests are located in places like Siberia and Alaska and have much colder temperatures, often below freezing.
Boreal forests are also known for having a significant role in carbon capture, and their frigid conditions accommodate unique animals like moose, reindeer, arctic hare, and polar bears. Tropical rainforests, which house a majority of the Earth’s plant and animal species, have a high amount of rainfall and enough trees to provide a dark, protected environment for fungi, jaguars, gorillas, and poisonous frogs. Temperate forests are home to more diverse animals adapted to summer, fall, winter, and spring, such as wolves, mountain lions, deer, squirrels, raccoons, and hibernating bears.
According to a study on carbon mapping published in Nature, letting forests regrow naturally through 2050 could potentially absorb up to 8.9 billion metric tons of CO2 from the atmosphere each year, all while maintaining the current level of food production.
What Is a Wood?
By the FAO’s definition, land not defined as “forest” that spans more than 0.5 hectares is considered “other wooded land.” Woods must have trees higher than 5 meters (16 feet) and a canopy cover of between 5% and 10% or a combined cover of shrubs, bushes, and trees over 10%. By U.S. National Vegetation Classification standards, woodland refers to vegetation dominated by trees with an open canopy, typically with 5% to 60% cover. By these standards, a wood becomes a forest once it gets dense enough to cover over 10% of its land with tree canopy.
It depends on where you are, as well. What North America calls “old-growth forests,” the United Kingdom calls “ancient woodlands,” referring to stands of trees that existed before the year 1600. In Australia, a woodland is an area with 10% to 30% tree cover, subdivided into tall woodlands with trees over 98 feet and low woodlands with trees under 33 feet.
These open canopies mean that more sunlight can reach the woodland floor, which is why woods are more likely to have more ground-dwelling animals (think: deer, raccoons, hedgehogs, rabbits), and forests typically contain animals that can live exclusively among the trees.