Canopy Tree Project
Fever Trees and Forest Pharmacies
January 5, 2026
For centuries, forests have stood as silent sentinels and humanity’s first pharmacy. Generations of herbalists — and today’s scientists — have turned to trees and plants to discover remedies that relieve pain, fight disease, and save lives.
In 2023, around 11 percent of the drugs that the World Health Organization considered “basic” and “essential” originated in flowering plants — and there were many more that originated from those that do not flower. Yet, as deforestation accelerates and biodiversity declines, we risk losing the wisdom hidden in these forests before we even discover them. Here are several tree-based medicines that demonstrate nature’s extraordinary pharmaceutical power.
Aspirin
Long before aspirin became a household name, the willow tree was used by Sumerians in pain management remedies as far as 4000 years ago. White willow bark contains salicin, which metabolizes in the body as salicylic acid. Salicylic acid in the body works by blocking cyclooxygenases, enzymes that produce inflammation, and preventing blood cells from sticking together, which reduces pain and fever.
In the early 19th century, scientists began isolating salicin from willow bark — with Johann Büchner isolating and naming salicin in 1828, Henri Leroux purifying it to treat rheumatism in 1829, and the Heyden Chemical Company launching large-scale production in Germany in the late 1800s. Aspirin as we know it today emerged when Bayer, a former German dye company, pivoted to pharmaceutical production.
Aspirin, acetylsalicylic acid, is on the World Health Organization’s Model List of Essential Medicines. The List includes medicines considered critical for addressing the most pressing global health needs based on their effectiveness, safety, and cost-effectiveness.
The Fever Trees: Antimalarials
Malaria is a life-threatening disease that is mostly found in tropical countries and spread to humans by some types of mosquitoes. Quinine was the first antimalarial drug. It is found in the bark of the cinchona tree, a tree native to the Andes region of South America. French chemists isolated quinine from the cinchona bark in 1820, establishing it as the treatment for intermittent fevers worldwide.
Quinine was strategically important to the Allied powers during World War II. The Japanese capture of the Dutch East Indies in 1942 cut the Allies off from the supply of quinine. This limited and halted Allied military operations in the Indo-Pacific region, as tens of thousands of soldiers were infected with malaria. This forced the military to turn to alternative antimalarials.
The 1960s created a need for the development of new antimalarial drugs, as drug-resistant malaria disabled U.S. military troops in Vietnam — at times, disabling more soldiers than combat. In 1969, Chinese scientist Tu Youyou was assigned to search for a cure in traditional medicine, eventually identifying and extracting artemisinin from sweet wormwood. This breakthrough earned Tu the Nobel Prize in Physiology or Medicine in 2015.
Today, the World Health Organization recommends artemisinin-based combination therapies — a combination of a fast-acting artemisinin derivative with a longer-lasting partner drug — as the first-line treatment for the deadliest strain of malaria. Quinine is no longer a first-line antimalarial, but it is still used today when other treatments cannot be used.
The Tree Oncologists: Anticancers
According to the World Health Organization, cancer encompasses a broad range of diseases that can occur in any organ or body tissue and are characterized by abnormal cell growth that invades other parts of the body. More than 65 percent of the medications used in cancer treatment originate in plants and their derivatives.
From 1960 to 1981, the National Cancer Institute and the U.S. Department of Agriculture (USDA) partnered to screen over 115,000 plant extracts from 15,000 different species, searching for natural compounds that could fight cancer. In 1962, USDA botanist Arthur Barclay collected a sample from the Pacific yew that enabled researchers to isolate paclitaxel, which stops cancer cells from dividing.
Today, paclitaxel is on the World Health Organization’s Model List of Essential Medicines as a drug that kills cancer cells. Paclitaxel is approved by the U.S. Food and Drug Administration to treat breast cancer, ovarian cancer, non-small cell lung cancer, and Kaposi sarcoma. Paclitaxel is one of the most important anticancer drugs.
Paclitaxel is not the only cancer fighting drug that comes from the trees. Camptothecin comes from the Camptotheca acumineta, or the “happy tree,” a deciduous tree native that is native to China. Camptothecin prevents cancer cells from replicating their DNA, killing the cells, and its derivatives include topotecan and irinotecan, which are used in the treatment of breast, ovarian, colon, lung, and colorectal cancer.
The Pharmacy We Cannot Afford to Lose
These four medicines represent just a fraction of what forests have given us. There is a clear connection between human health and forest health.
More than half of all medications derive from 50,000 known medicinal plants — with up to a fifth of these at risk of extinction due to deforestation. Thus, the loss of forests doesn’t just mean losing trees — it means losing knowledge and losing the medicine cabinet of future generations.
Forest conservation is healthcare infrastructure. Protecting biodiversity is investing in medical research. When we save forests, we’re not just preserving beauty or fighting climate change — we’re maintaining nature’s laboratory, keeping open the possibility that the next revolutionary medicine is growing silently in a forest somewhere, waiting to be discovered. Please consider donating to our Canopy Tree Project to help us plant trees to combat climate change, protect biodiversity, and support communities worldwide.
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