A botanist’s legacy for Philippine plants and human health

November 15, 2024

As we rush to school, work, or in-between, we overlook the greenery around us. It’s all just a blur, plants. We pass by plant life under our feet, over our heads, and around our homes.

Others, like myself, love green spaces. We enjoy time at the park, or a trek up a mountain in the province. Leave it to the Japanese to have a word for forest bathing: shinrin-yoku.

And then there was Leonard Co. Not only did he dive into the forest because it made him happy, he also saw the forest as an ancient pharmacy for people. He was regarded as a “human library” of Philippine plants and trees. A colleague of mine once shared her awe of his ability to identify trees down to the family, genus, or even species name.

Leonard Co - photo from Philippineplants dot org — A young Leonard Co conducting research on the field. Photo from Philippineplants.org.

The world’s oldest healthcare system: nature

Apparently around 40% of pharmaceutical products are from nature, according to the World Health Organization. The healing abilities of trees and plants are not excluded to forest bathing or nutritious vegetables. They literally take our pain away.

Asprin is derived from the willow tree, whose bark was used as far back as 3,500 years ago as a pain reliever. Morphine relieved soldiers of pain during World War II. It comes from the opium poppy, Papaver somniferum, one of humanity’s oldest medicinal plants.

The Philippines’ Department of Health lists 10 plant species officially recognized as medicinal sources. This includes Lagundi (Vitex negundo), Sambong (Blumea balsamifera), Tsaang gubat (Ehretia microphylla), among others.

Lagundi (Vitex negundo) on the campus of the University of the Philippines in Diliman — Lagundi (Vitex negundo) has long been used in the Philippines to treat coughs, asthma, and fevers. This particular plant can be found on the campus of the University of the Philippines, Diliman.

Spreading seeds of knowledge

Like many of our precious botanists, Leonard Co had long been an advocate of both the medicinal and ecological benefits of plant life. He loved plants so much that much of his life was dedicated to it.

When Co was a botany student, he was one of the founders of the University of the Philippines Botanical Society. Together they published a “Manual on some Philippine medicinal plants” in 1977. As a taxonomist, he discovered, collected, and named several species of plants new to science. A species belonging to some of the largest flowers in the world was eventually named after him: Rafflesia leonardi.

Fully open male flower of Rafflesia leonardi, named after Leonard Co. Photo by Julie Barcelona. — Fully open male flower of *Rafflesia leonardi*, named after Leonard Co. Photo by Julie Barcelona.

During the 80s, amidst political unrest in the Philippines under Ferdinand Marcos, Leonard Co left the University of the Philippines to serve indigenous communities in Northern Luzon. He soon co-founded a Baguio-based NGO that helped publish a book on “Common medicinal plants of the Cordillera Region” in 1989.

In 2007 he founded the Philippine Native Plants Conservation Society, Inc. or PNPCSI and became its first president. It was an extension of his personal advocacy: the use of native plants in forest restoration, student mentorship, and public education. He gave plant ID assistance free of charge. Fellow scientists and students asked him for help with plant identification via e-mail, text, or Facebook.

Loss in Leyte

Like many places in the Philippines, Kananga in the province of Leyte has lost a substantial amount of forest over the decades. Leyte itself is struck frequently by typhoons every year, including Super Typhoon Yolanda (international name Typhoon Haiyan) whose storm surges made headlines when it hit the province in November of 2013.

On November 15, 2010, Leonard Co was in Kananga with a team composed of fellow experts and forest guides. This included forest guard Sofronio Cortez, Julius Borromeo from the Tongonan Farmers Association, forest guide Policarpio Balute, and forester Roniño Gibe. They were conducting tree seedling collection for BINHI, a reforestation project by the Energy Development Corporation or EDC.

As they were looking for mother trees, or trees whose seeds and wildlings are used for tree nurseries, a shooting incident occurred whose details remain muddled and unclear to this day. By the end of the tragedy, three people died: Sofronio Cortez, Julius Borromeo, and Leonard Co. Co himself suffered 3 gunshot wounds to the back.

The military cited that a crossfire had occurred between the Philippine Army’s 19th Infantry Battalion and communist fighters of the New Peoples Army or NPA.

A small memorial dedicated to Leonard Co can be found on the campus of the University of the Philippines, Diliman. It sits at the foot of a dita tree (Alstonia scholaris). — A small memorial dedicated to Leonard Co can be found on the campus of the University of the Philippines, Diliman. It sits at the foot of a dita tree (*Alstonia scholaris*).

One of the survivors, Policarpio Balute, stated that there was no indication of a fire fight as the military claimed. On December 8, 2010, a team of scientists visited the site where the incident took place. They found that the shots had come from where the army soldiers were positioned. They also found that the military failed to provide immediate medical aid to Borromeo after the shooting, despite the pleas of one of the two survivors, Roniño Gibe.

Late scientist Perry Ong and fellow biologist Nina Ingle later wrote of Leonard Co, “It is ironic that he was gunned down while doing the work that he loved, identifying tree species in the middle of a remnant forest that he was trying to restore.”

According to Global Witness, the Philippines has been the 3rd deadliest place in the world to be an environmental defender. It recorded 298 documented killings between 2012 and 2023.

Co and members of his team were killed in 2010.

Philippines is 3rd in most deadliest countries for environmentalists - Global Witness — A chart from a September 2024 report by Global Witness showing the numbers of documented killings of environmental defenders around the world. The Philippines ranked 3rd.

A legacy to be continued

Leonard Co was known as a “human library” of plant species, because of the amount of study and collection he conducted throughout his life.

He was an active plant taxonomist, or someone who specializes in classifying and sorting species. Taxonomy is important because it allows policy makers to determine how natural resources should be conserved or used.

The Philippines’ protected area system for example involves knowing what specific species in particular areas are threatened. The mantra, “you cannot protect what you do not know,” greatly summarizes the importance of taxonomy. The significance of plants in medicine for example is another reason why taxonomy is important.

Protected area PP 1636, taxonomy and science is important for protected area policy — Forest of Protected Area PP 1636, located in the Sierra Madre in Northern Philippines. Many challenges are faced by both forest and communities in protected areas, but having a basis in policy and law allows for greater protection.

Leonard Co collected more than 6,000 specimens under his name, in addition to the specimens filed in the various consultancy projects he was involved in. He had 11,000 plant photographs, and undertook the huge task of updating the most comprehensive list of Philippine plants ever made. “An Enumeration of Philippine Flowering Plants” was a 4 volume book compiled over 20 years. It was the most ambitious work of American botanist Elmer Merrill who completed the work during the American colonial period in the Philippines.

Since it was long outdated, Leonard Co began annotating or making notes on the species listed. Eventually he had an updated checklist organized in Microsoft Word files, whose information would be used to help conservation initiatives throughout the years despite being unpublished.

Example of Leonard Cos annotations in Merrills book — Page 21 of Leonard Co’s copy of Elmer Merrill’s “An Enumeration of Philippine Flowering Plants” with his handwritten updates. Image from Co’s Digital Flora of the Philippines: plant identification and conservation through cybertaxonomy by JF Barcelona et al.

Had he continued to live, his notations and photos would have been part of the most updated and comprehensive list of plant species in the Philippines. It would have likely enshrined most of the estimated 10,000 species of plants in the country, for use in everything from environmental policy to medicinal research.

Instead, the long arduous process of understanding the Philippines’ plants now goes to a new generation of botanists, environmentalists, and nature lovers.

Co’s Digital Flora of the Philippines is the product of this hard work. It is a publicly accessible website that aims to provide up-to-date photos and data of Philippine plants. You can see it now at Philippineplants.org. The website’s foundation was formed from Leonard Co’s unpublished checklist and his collection of plant photos. It is now a collaborative effort by students and experts in the Philippines and all over the world. A Facebook group allows researchers and students to upload photos and data of Philippine plants from the field.

Co’s family and the researchers behind the project shared in a paper: “…His death necessitated the publication of his files to prevent the loss of the wealth of taxonomic data that he generated throughout his career. In this context, publishing the checklist on a website provided an opportunity to continue to develop this work-in-progress as a living document.”

They also added on the website the importance of understanding, “…The very life-support system that sustains us, and the material basis of indigenous knowledge and culture of Filipinos.”

As of this writing, PNPCSI had just voted in its latest board of trustees for 2025. A series of on and offline events had already been conducted by its members throughout 2024.

I had the privilege of going on a few “tree treks” with PNPCSI. It was there that I learned about the term “plant blindness”, thanks to David Ples who was previously a PNPCSI trustee. Plant blindness refers to what happens when people pass by plants and trees in their daily lives without acknowledging them or their importance.

Leonard Co’s legacies continue to attract and inform botanists and environmentalists who continue to share plant knowledge with more and more people. Maybe one day we’ll do away with “plant blindness”, and bring to light the importance of plants under our feet and over our heads.

In the face of climate change, species loss, and the spread of zoonotic diseases like covid, the movement to understand our environment requires more and more people to see the truth. Doing so may be the best medicine for humanity, to help take our collective pain away.

Budding botanists and members of Philippine groups such as PNPCSI and Haribon Foundation — Budding and full-grown botanists and plant lovers gather around a small memorial dedicated to Leonard Co on the campus of the University of the Philippines, Diliman. The memorial sits at the foot of a dita tree (*Alstonia scholaris*), also known as the “Scholar’s Tree”. A great analogy to the research conducted by Leonard Co and its legacy for future scholars.

Learn more about Leonard Co, and how the Philippines’ lost one of its most valuable researchers in the movement to conserve our forests. Watch the documentary “Walang hanggang buhay ni Leonard Co.“