A glossary
of my work

The upper layer of a forest, formed by the crowns of the tallest trees. It holds roughly half of all life on land, yet remains one of Earth's least-explored ecosystems — which is why I call it the Eighth Continent.

My name for the forest canopy. It's a real, largely unmapped world of its own, layered above the forest floor most people think of as "the forest."

An explorer or scientist who studies the forest canopy. The word combines the Latin "arbor" (tree) with the Greek "naut" (sailor) — someone who sails in trees. I coined the term, and I'm widely described as the world's first arbornaut.

The methods and equipment that get a researcher safely into the tree crowns: ropes, harnesses, walkways, and platforms. Before these existed, almost nothing above the forest floor had ever been studied up close.

The climbing method I used to invent my own way into the canopy: a slingshot to get a line over a high branch, a caving harness, and a rope. It's still one of the core ways arbornauts get into the treetops.

An elevated, permanent structure — bridges and platforms strung through the tree crowns — that lets researchers, students and visitors reach the canopy without climbing. Mission Green's core infrastructure.

A plant that grows on another plant, usually up in the canopy, without being a parasite. Orchids, ferns, mosses, and bromeliads are epiphytes — an enormous amount of a forest's plant life never touches the ground.

A family of epiphytes, related to the pineapple, that grow directly on canopy branches. Their leaf structure often collects rainwater, creating tiny pools that support their own miniature ecosystems.

When a tree or forest loses its canopy foliage and branches from the top down, often from disease, pests, or drought. I identified the cause of a major eucalypt dieback epidemic in Australia in the 1980s: Christmas beetles.

What I called myself in my early fieldwork: working out exactly what was eating a tree's foliage, and why, one leaf at a time. It's also how I discovered that most canopy insects feed at night.

The nonprofit I founded — Tree Research, Education, and Exploration — so that access to the canopy would not end with my own climb. It builds canopy walkways and supports research, education and exploration toward global forest conservation.

Research carried out with the direct participation of the public rather than professional scientists alone. I've led over 35 citizen-science expeditions to the Amazon, and citizen science underpins much of Mission Green's data.

An intensive, short-timeframe survey where scientists and volunteers try to record every species in a given area. A Mission Green bioblitz at a canopy walkway in Malaysia produced the data behind a UNESCO World Heritage designation.

TREE Foundation's flagship initiative to protect the world's most biodiverse forests by building canopy walkways that combine research, education, ecotourism, and local stewardship.

The measurable framework behind Mission Green: 12 canopy walkways in the 12 highest-biodiversity forest hot spots, over 12 years, with $12M invested, supporting 120 local community members and 1,200 student explorers.

A region with an exceptionally high concentration of species found nowhere else, and under exceptional threat. Mission Green targets the hot spots where a single canopy walkway does the most good.

Ethiopia's last fragments of native forest, preserved because they surround Coptic Orthodox churches — are the only patches of original tree cover left in a country with under 5% forest remaining. I created the world's first trust-partnership with the Coptic priests to protect them; we've saved over 100 so far.

The mark every member of the Women's Coalition receives to use publicly — on a profile, a site, a slide deck — so membership is visible rather than private.

The Fund's model, in order: give girls and women real access to the canopy, turn that access into concrete conservation action, and hand long-term stewardship to local and Indigenous communities.

A donor or partner who backs the Fund at its earliest stage, before the track record exists that makes later support an easier decision. The Fund is actively seeking founding supporters now.

A microscopic, nearly indestructible eight-legged animal that lives in the moss and lichen of the canopy. I had two new species named after my sons — one, Doryphoribius elleneddiei, became a wedding gift.

An Australian scarab beetle. I found that Christmas beetles were the pest ultimately responsible for a major eucalypt dieback epidemic I researched in the 1980s.

A moth whose caterpillars can strip a forest canopy bare. My students discovered one of its natural predators, work that got every one of them a scholarship to grad school.

A canopy-dwelling primate found in Southeast Asian rainforests, including the ones Mission Green works to protect in Malaysia.

A large, pale-green silk moth and one of the more striking residents of the canopy.

A moth whose wings are camouflaged to look exactly like a leaf, invisible against the foliage until it moves.

A slow-moving canopy mammal that spends nearly its entire life in the tree crowns, rarely descending to the ground.

A venomous Australian snake. A colony once bred in the outhouse on our farm in Australia.

A great ape found in the rainforest canopies of Borneo and Sumatra. I've led National Geographic trips to see them.

A scientist who studies arachnids — ticks, spiders, scorpions, mites, and harvestmen.

A family of birds that build a ground nest and decorate it with colorful objects to attract a mate.

A member of the general public who assists scientific research, either by making observations or collecting data.

When birds sing actively at sunrise, creating a symphony of songs. In temperate forests this only occurs in spring or early summer, when birds sing to attract a mate or announce their territory.

Dichloro-diphenyl-trichloroethane, a chemical developed in 1939 to fight insect-borne disease and crop pests. It accumulated in the fatty tissue of animals, not just insects, and was banned in many countries in the 1970s.

Trees that lose their leaves seasonally and regrow new foliage each spring.

A forestry device that measures the expansion or shrinkage of tree trunks, used to determine a tree's water status and health.

An organization that provides volunteers for scientific expeditions — extra eyes and ears for the scientists, and a unique insight into field biology for the citizen volunteers.

Where organisms at the edge of a forest have greater exposure to extreme weather — hotter, windier, or icier — than those further in.

A rainforest tree that grows higher than the rest of the canopy, towering above it. The tornillo tree and the great kapok tree are examples.

A species native to one specific place and found nowhere else. Lemurs, for example, are endemic to Madagascar.

The science of studying insects.

The art of cooking and eating insects.

Someone who studies the uses of plants for medicine.

Trees that retain their leaves all year, shedding only a portion of their canopy at different times.

The technical word for insect poop. Arbornauts (and gardeners) see it on leaves and flowers as a sign the plant has been chewed by insects.

An award of funding to sponsor a specific project, usually written in a competitive process and awarded for a short time frame.

A dried collection of plants, labeled with the species name, where it was collected, by whom, and notes such as color and height.

A scientist who studies reptiles and amphibians.

An animal that only feeds on one, or maybe two, food sources.

A plant in the pepper family, native to the Pacific Islands. Islanders make a beverage from its root with anesthetic or sedative properties, often used in ceremonies.

Light detection and ranging: a remote sensing method that uses aircraft-mounted cameras to study the earth, including forest canopies, from above.

The practice of planting one crop instead of a diversity of crops. Cheaper to plant, but it encourages insect pests and often leads to pesticide use that harms biodiversity beyond the target insect.

The study of the seasonal calendar of natural activities triggered by light, rainfall, and temperature — for trees, this includes budburst, leafing, flowering, and leaf fall.

Replanting and restocking species to recreate an ecosystem after it has been destroyed, usually by human activity. Most existing American forests are the product of rewilding after clearing.

Wildflowers that grow early in spring on the forest floor, before the trees overhead leaf out, so they can gain enough sunlight to produce seeds. Violets, jack-in-the-pulpit, and trillium are examples.

A large, dominant root that stores water, letting a plant survive drought and extreme weather.

Also known as the Sahyadri, a mountain range in India covering just over 60,000 square miles. One of India's major watersheds, declared a UNESCO World Heritage Site in 2012, and home to at least 325 globally threatened endemic species.