The first light of morning filters through the Sembuak forest canopy as the women of Dayak Abay Sembuak community begin their familiar walk. Some carry woven baskets. Others balance hoes and machetes over their shoulders.  

The journey is routine, repeated almost every day for decades. Yet every step follows an invisible map that exists only in memory, one passed quietly from mothers to daughters, grandmothers to grandchildren. Like a mother tongue, this knowledge is learned long before it is ever explained—through observation, repetition, and trust.

For these women, the forest is not wilderness. It is home.

Every morning, they head to their fields to plant rice, sweet potatoes, corn, and other vegetables. They gather firewood for cooking and timber for repairing their homes. Hidden beneath the towering trees, they also find something far less visible but no less essential: the plants that have healed their families for generations.

When someone develops a cough, they gather the young leaves of jabu, lightly roast them over a fire, and drink the liquid extracted from the warmed leaves. When an infection needs treating, they harvest natu leaves, crush them into a paste, and apply it directly to the wound to aid healing. The names are spoken with familiarity, carried in conversations rather than textbooks, and remembered through practice rather than prescriptions.

"Our customary forest serves our community," says Salma, a member of Dayak Abay Sembuak community, Malinau, North Kalimantan. "We find wood here, food here, and medicines here."

For Dayak Abay Sembuak community, the forest is a living pharmacy.

The medicinal plants scattered beneath its canopy are not isolated remedies, but part of a healthcare system refined over generations through careful observation of nature. Long before modern medicine reached these villages, customary women had already learned which leaves reduce fever, which roots ease infection, and which plants help restore sleep. They continue to carry that knowledge today as mothers, farmers, caregivers, and teachers.

Modern medicine is increasingly revealing the value of this relationship. According to the World Health Organization, around 40 percent of pharmaceutical medicines are derived from or inspired by natural products1, while many widely used medicines—including aspirin, quinine, and several cancer treatments—trace their origins to compounds first discovered in plants.

This year's International Day of the World's Indigenous Peoples carries the theme "Honouring Indigenous Midwives: Safeguarding Life and Well-being." While the spotlight is on Indigenous midwives, the message extends to women in the customary communities more broadly as custodians of knowledge and guardians of community well-being. From supporting mothers and newborns to preparing traditional medicines and teaching children about the forest, they sustain living knowledge systems that continue to nurture both people and nature.

The story unfolding in Dayak Abay Sembuak echoes far beyond this corner of Indonesia. Around the world, customary communities live on roughly 22 percent of the Earth's land surface, territories that contain around 80 percent of the planet's biodiversity. These landscapes have remained biologically rich because they are more than forests. They are living homes, shaped by generations of stewardship, respect, and intimate knowledge of nature.

Women are often at the heart of that relationship.

Their knowledge is rarely written down. Instead, it is carried in memory and passed from one generation to the next, often during the ordinary rhythms of daily life. A child learns while following her mother into the forest. She watches where to stop, which leaves to harvest, which plants must never be disturbed, and how much can be taken without harming what remains.

"If we don't teach them, they won’t know," says Halina, one of the women in Dayak Abay Sembuak community.

When an elder passes away before passing on what she knows, the loss extends beyond one family. An entire library disappears.

Unlike books, these libraries cannot be rebuilt.

They exist in memories of forest paths, in the names of plants spoken only in Indigenous languages, in hands that instinctively know which bark relieves a cough and which leaves draw out infection. They are living archives of biodiversity, culture, language, and healing, preserved beneath the forest canopy itself.

That is why customary forests matter.

They are not simply forests owned by customary communities. They are places where culture continues to be practiced, where ecological knowledge evolves across generations, and where the health of people and the health of nature remain inseparable.

Yet these forests continue to face mounting pressures. Competing land-use interests, overlapping claims, and expanding commercial development increasingly threaten landscapes that customary communities have cared for over centuries. When customary forests are lost, the disappearance is measured not only in hectares, but also in traditions, languages, and medicinal knowledge that may never be recovered.

Recognizing the vital role of customary forests in safeguarding biodiversity, cultural heritage, and indigenous knowledge, the Government of Indonesia has been accelerating the recognition of customary forests since 2016. Supported by the Government of Norway, UNDP works alongside national and subnational governments, customary communities, civil society organizations, and academia to help accelerate the recognition of 1.4 million hectares of customary forest across Indonesia.  

The initiative goes beyond drawing boundaries on a map.

It strengthens the identification and verification of customary communities, supports local governments throughout the recognition process, and helps ensure that customary forests receive the legal protection needed for communities to continue managing them according to their traditions. By securing these forests, the initiative also helps safeguard the knowledge systems, cultural practices, and traditional medicines that depend on them.

For Salma, however, the future is not measured in hectares or legal documents. It is measured by whether the next generation will still know the forest as she does. She hopes her children will continue planting rice and sweet potatoes, recognize medicinal plants by name, and inherit the same forest that has sustained generations before them.  

"Our hope," she says, "is that we protect this customary forest together so our children and grandchildren can continue to enjoy its benefits."  

Her words are a reminder that recognizing customary forests is ultimately about protecting a living knowledge system. Every forest that remains under Indigenous stewardship safeguards generations of experience about healing, sustainable farming, and living in balance with nature.  

The women of Dayak Abay Sembuak are not only protecting a forest. They are protecting the knowledge that gives it meaning. In every medicinal plant they identify, every child they teach, and every tradition they pass on, they remind us that conserving nature is also about safeguarding the wisdom that has enabled people and forests to thrive together for generations.