Tree identification resources by country

Naming a tree is the first step in most tree work, and it is a topic on the ISA Certified Arborist exam: the program guide, revised August 2025, lists Tree Identification and Selection at 9% of the questions. This page lists official and university sources by country.

The list is short on purpose. Tree names change between regions, so a name from one country's site may not match a name used in another. For the biology words used in keys, see the tree biology guide.

United States

The federal tool is the USDA PLANTS Database, hosted by the USDA Natural Resources Conservation Service. Its home page says it provides standardized information about the vascular plants, mosses, liverworts, hornworts and lichens of the United States and its territories. It lists these search types: characteristic, duration, fact sheets and plant guides, group, growth habit, image, invasive and noxious, rarity, state and wetland.

The home page does not state a price. The offerings are on the PLANTS Database home page.

Canada

The source listed is a provincial one. The British Columbia Ministry of Forests Tree Book says its information will help you identify the native trees in your neighbourhood and understand why they grow where they do. It says British Columbia has about 40 different species of native trees, though you will not find all of them everywhere.

The Tree Book offers an index of trees and keys for identifying trees.
Its page on what to look for says many trees look the same from a distance, and that up close you start to recognize differences.
The book is offered as a PDF download of 12.9 Mb, with a link to order a copy. The page does not state a price.

It covers British Columbia only. See the BC Tree Book home page.

United Kingdom

Forest Research is the research agency of the Forestry Commission. Its Tree Species Database holds information on over 60 tree species that are either widely grown in British forests now or could play an increasing role in the future. The page describes it as information on species, not as an identification key. The database is described on the Forest Research species database page.

The Woodland Trust is a charity, and this part describes its own pages. It says the United Kingdom has at least fifty species of native trees and shrubs, and many more introduced non-native trees. Its identification page tells readers to piece the clues together: the overall shape and size of the tree, bark, leaves or needles, flowers, fruits, leaf buds and twigs. It says the more features you can see, the more accurate your identification will be. In winter, it says, broadleaf trees need twigs, leaf buds and bark.

The charity's own page offers an A-Z identification guide to British trees, from natives to naturalised and widely planted non-native species, and says its free tree identification app is available for Android and iOS. See the Woodland Trust identification page.

Australia

Australian identification sits with the state and territory herbaria and a national records site. The pages are below.

Resource	Run by	What the page says
PlantNET	National Herbarium of New South Wales	Name search by scientific or common name, and dichotomous keys based on the Flora of New South Wales
VicFlora	Royal Botanic Gardens Victoria	A guide to the wild plants of Victoria, free of charge
Atlas of Living Australia	National open data site	Open access to biodiversity data. A tool shows what species live near a place entered
EUCLID	Copyright held by CSIRO and the Director of National Parks	A key to eucalypts, Edition 4 from 2015

PlantNET

The PlantNET page lists a plant name search and traditional dichotomous keys. It also carries a warning: the site presents a demonstration of one approach to an electronic flora, its data have not been fully checked for consistency and are not fully up to date, and it is to be regarded as a prototype, not necessarily an authoritative resource. The warning is on the PlantNET introduction page.

VicFlora and the Atlas

The VicFlora home page says the species profiles and identification tools are provided by Royal Botanic Gardens Victoria free of charge, and lists multi-access keys. See the VicFlora home page. The Atlas of Living Australia is a records site, not a key: it says its "Explore your area" tool takes a street address, GPS coordinates, postcode or place name and shows what species live near you. See the Atlas home page.

EUCLID for eucalypts

The EUCLID foreword says eucalypts are the dominant trees in Australia and that over 890 species and subspecies are currently recognised. Its about page says Edition 4 is internet based and hosted by Identic Pty Ltd of Brisbane, and that copyright is held by the Director of National Parks and CSIRO, which together make up the Centre for Australian National Biodiversity Research. The edition linked here is the hosted one. See the EUCLID about page.

New Zealand

The New Zealand Plant Conservation Network is a plant conservation network. It says its role is to provide information and support to plant conservation practitioners, landowners and managers. Its plant identification page lists three kinds of help: written and pictorial descriptions, asking an expert, and plant keys. It adds that collecting plants is often discouraged and a detailed photograph may be taken instead. It also points to the plant identification and information service of Manaaki Whenua Landcare Research. The details are on the network's plant identification page.

Flora of New Zealand, at nzflora.info, describes itself as the definitive reference to New Zealand plants, with the latest scientific information about indigenous and naturalised plants found in New Zealand. See the Flora of New Zealand site.

The Landcare Research home page says Manaaki Whenua has amalgamated with AgResearch, Plant and Food Research and Scion to form the Bioeconomy Science Institute.

At a glance

Country	Pages listed	Not listed
United States	USDA PLANTS home page	Forest Service, state and university pages
Canada	BC Tree Book	Federal and other provincial pages
United Kingdom	Forest Research, Woodland Trust	Kew
Australia	PlantNET, VicFlora, Atlas, EUCLID	Other state herbaria
New Zealand	Plant Conservation Network, Flora of New Zealand	Landcare identification service

A name from a website is a starting point. Where a decision rests on the species, such as a protected tree or a regulated pest, the agencies in the tree protection laws guide and the pests and diseases guide say who to ask.