Forests serve an enormous range of purposes, from producing the wood and paper products we use every day to regulating the planet’s water cycle and housing the majority of life on Earth. Roughly 1.2 billion people rely directly on forest-based farming systems for their livelihoods, and the global trade in wood products alone reached $244 billion in 2019. But the uses of forests extend far beyond economics into medicine, climate stability, clean water, and human health.
Timber, Paper, and Wood Products
The most visible use of forests is as a source of raw materials. Timber harvested from forests becomes lumber for construction, furniture, flooring, and fencing. It’s also processed into paper, cardboard, packaging, and engineered wood products like plywood and particleboard. Global consumption of roundwood (logs before they’re processed) is projected to reach about 2.2 billion cubic meters by 2030, a roughly 10% increase driven largely by population and economic growth in Asia. Woodchip consumption, used primarily for paper pulp and biomass energy, is expected to jump by about 40% over the same period.
China has been the largest driver of this expansion. Between 1990 and 2019, Chinese imports of wood products grew by 760%, reaching $49 billion. Beyond industrial timber, forests also supply fuelwood, which remains a primary cooking and heating fuel for hundreds of millions of households in lower-income countries.
Food, Income, and Daily Survival
For communities in rural and low-income regions, forests function as a grocery store, pharmacy, and building supply outlet rolled into one. People harvest wild fruits, nuts, mushrooms, honey, bushmeat, and edible insects directly from forest ecosystems. They also collect materials like bamboo, rattan, rubber, and resins to sell or use at home. About 1.2 billion people worldwide depend on agroforestry, a practice that integrates trees into cropland and pasture to boost yields and diversify income. In many tropical countries, these forest-derived products make the difference between food security and hunger during lean agricultural seasons.
Habitat for Most of Earth’s Species
Forests are the planet’s richest terrestrial habitat. Tropical forests alone harbor 62% of the world’s terrestrial vertebrate species, more than twice the number found in any other land-based biome. That includes mammals, birds, reptiles, and amphibians, many of which exist nowhere else. Temperate and boreal forests add thousands more species of plants, fungi, insects, and microorganisms. When forests disappear, these species lose the specific conditions they evolved to depend on: the canopy layers, the deadwood, the understory shade, and the soil ecosystems beneath the surface.
A Source of Modern Medicine
Some of the most important drugs in modern medicine trace back to forest plants, often ones that indigenous communities had used for centuries before scientists studied them. Quinine, the foundational malaria treatment, comes from the bark of the cinchona tree in the Andean rainforests, where the Quechua people used it long before European contact. Vincristine and vinblastine, two drugs used to treat childhood leukemia and Hodgkin’s disease, are derived from the rosy periwinkle found in Madagascar’s rainforests.
A muscle relaxant widely used in surgery comes from curare vines in the Amazon, originally applied by indigenous hunters as arrow-tip poison. Cortisone, an ingredient in birth control pills, was developed from wild yams in South American tropical forests. Even a compound showing activity against HIV was isolated from a rare tree species in the rainforests of Sarawak, Malaysia. These examples represent only a fraction of what forests contain. The vast majority of tropical plant species have never been screened for pharmaceutical potential.
Protecting Soil and Preventing Erosion
Forests anchor soil in place with their root systems while their canopy breaks the force of rainfall before it hits the ground. The difference in erosion rates between forested and unforested land is dramatic. Studies comparing the two found that forested land loses an average of about 0.4 tons of soil per hectare each year, while agricultural land loses roughly 22 tons per hectare annually. Bare land performs even worse, with soil loss ranging from about 10 to over 109 tons per hectare per year depending on slope and rainfall.
In northern Brazil, recently deforested areas lost 115 tons of soil per hectare, while nearby land that had regrown shrubs and trees lost just 1.2 tons. Slash-and-burn farming produces erosion rates 20 times higher than natural forest. This matters because topsoil takes centuries to form and carries the nutrients that sustain agriculture. Once it washes away, the land becomes far less productive.
Driving Rainfall and the Water Cycle
Forests don’t just receive rain. They help generate it. Trees pull water from the soil through their roots and release it as vapor through their leaves, a process called transpiration. This moisture rises, forms clouds, and falls again as precipitation downwind. In the Amazon basin, this recycling mechanism is so powerful that the forest effectively creates its own weather. Research published in Nature Communications found that large-scale deforestation in the southern Amazon has measurably reduced regional rainfall by suppressing this moisture recycling.
When forests are removed, the atmosphere dries out and becomes more stable, meaning fewer rain-producing updrafts form. Moisture that would have recycled locally instead flows out of the region entirely. Intact forests, with their tall, complex canopies, sustain intense mixing between the land surface and the atmosphere, keeping the air humid and the rain falling. This has implications well beyond the tropics: forests in many parts of the world contribute to the water supplies that cities and farms depend on downstream.
Reducing Stress and Improving Health
Spending time in forests produces measurable changes in the body. A large Japanese study across 24 forests found that walking or simply sitting in a forest environment lowered salivary cortisol (the body’s primary stress hormone) by 13 to 16% compared to spending time in a city setting. Forest visitors also showed lower blood pressure, lower pulse rates, and a shift in nervous system activity toward the “rest and digest” state rather than the “fight or flight” response.
This practice, known in Japan as shinrin-yoku or forest bathing, has become a recognized approach to stress reduction. The effects aren’t subtle or subjective: they show up consistently in physiological measurements. Forests also improve air quality by filtering particulate matter and producing oxygen through photosynthesis, which has localized health benefits for nearby communities, particularly in urban areas adjacent to parks and green belts.
Carbon Storage and Climate Regulation
Trees absorb carbon dioxide as they grow, locking it into their wood, leaves, roots, and the surrounding soil. This makes forests one of the planet’s largest carbon sinks, counterbalancing a portion of human greenhouse gas emissions. When forests are cut or burned, that stored carbon is released back into the atmosphere, which is why deforestation accounts for a significant share of global emissions. Keeping existing forests standing, and allowing degraded forests to regrow, is one of the most cost-effective tools for slowing the buildup of carbon dioxide in the atmosphere. Old-growth forests are particularly valuable in this role because they store carbon in massive trunks and deep soils that took centuries to accumulate.
Recreation, Culture, and Tourism
Forests are among the most visited natural landscapes on Earth. Hiking, camping, birdwatching, hunting, fishing, and mountain biking all depend on forested land. National and regional parks built around forest ecosystems generate billions in tourism revenue and support local economies in rural areas that have few other industries. Beyond economics, forests hold deep cultural and spiritual significance for indigenous communities worldwide, serving as sites for ceremonies, storytelling, and the transmission of traditional knowledge across generations. For many urban residents, nearby forests and woodlands are the most accessible form of contact with the natural world.