Running a business
Approved contractor and credential-check schemes for tree work
Some associations assess whole tree businesses, and some run a search that shows whether a person holds a credential.
For tree owners
The questions tree owners ask about hiring, costs, neighbours, storms, stumps and their own trees, each answered with what the named official sources say. These pages are not advice about any tree: for that, ask a qualified arborist or the office a page names.
45 pages in this topic. Each guide names its sources and the date they were read.
Hiring an arborist
Open
Running a business
Checking a tree company: public registers and licence lookups by country
Free public lookups can show whether a tree business is registered, licensed, covered for injury or has a safety record.
For tree owners
Hiring an arborist: what the trade bodies say to look for
Tree owners are told by the International Society of Arboriculture, the Tree Care Industry Association, the Arboricultural Association and the New Zealand Arboricultural Association what to look for in a tree company.
For tree owners
Licensed, certified, accredited, insured: what each word means for a tree owner
Tree companies describe themselves with four different words, and each one comes from a different kind of body.
For tree owners
Reading a tree quote: what the trade bodies and consumer offices say it should list
Trade bodies in the United Kingdom, the United States and New Zealand, and two state attorney general offices, each list what a written tree quote or contract is said to cover.
For tree owners
Where to complain about a tree company: what two licensing boards and two consumer offices say
The California Contractors State License Board, NSW Fair Trading and GOV.UK each publish where a customer takes a complaint about a tradesperson.
Is my tree dying or safe
For tree owners
Branches dying back from the tips: what the sources say it may indicate
Iowa State Extension, UConn Extension and University of Minnesota Extension each list causes of branch dieback.
For tree owners
Cracks in a trunk or a leaning tree: what the sources say it may indicate
Alabama Extension, University of Kentucky Extension and ISA each describe cracks and lean in trees.
For tree owners
Holes in a trunk or bark: what the sources say it may indicate
UConn Extension, Purdue Extension and Iowa State Extension each describe holes in tree bark.
For tree owners
Is my tree dying? What university pages and ISA say the signs may indicate
Extension services at two US universities, a Tennessee Tech University web page and the International Society of Arboriculture describe signs that owners notice on trees and what each sign may point to.
For tree owners
Is this tree safe? What the sources say about tree risk and who assesses it
No page can say whether a particular tree is safe.
For tree owners
Leaves browning or turning color early: what the sources say it may indicate
Utah State University Extension, the Missouri Botanical Garden and NC State Extension each describe leaves that scorch, yellow or colour early.
For tree owners
Mushrooms at the base of a tree: what the sources say they may indicate
The International Society of Arboriculture, the University of Minnesota and Oregon State University each describe fungus growing at the foot of a tree.
For tree owners
Sap or ooze running from a trunk: what the sources say it may indicate
The University of Maryland Extension and Utah State University Extension each describe liquid running out of cracks and wounds on a tree.
For tree owners
Tree consultant or tree surgeon: who the tree bodies say gives which advice
The Arboricultural Association draws a line between the arborist who does the work and the consultant who assesses and advises.
Neighbour issues
Law & permits
Entering a neighbour's land for tree work: what the statutes say
Three statutes in the United Kingdom and Queensland deal with who may go onto a neighbour's land to work on a tree or hedge: a court access order in England and Wales, tribunal orders in Queensland, and the entry powers of councils under the high hedge Acts.
Law & permits
Neighbour tree law: what the statutes and official pages say, place by place
Which statutes and official pages deal with a neighbour's tree or hedge in the United Kingdom, Ireland, New South Wales, Queensland, Victoria, Western Australia, New Zealand, British Columbia and seven US states, with the section numbers.
For tree owners
Who pays when a neighbour's tree falls on a house: what US state insurance regulators say
Five US state insurance regulators publish consumer answers on a tree that falls from next door onto a house, a fence or a car.
Storms and emergencies
For tree owners
A tree is down: who the official sources say to call, by situation
When a tree comes down in a storm, the International Society of Arboriculture, a Victorian council, Energy Safe Victoria and Manitoba Hydro each say who to call and what to keep clear of.
For tree owners
Before a storm: what the sources tell tree owners about their trees
The International Society of Arboriculture, the University of Florida extension service and Miami-Dade County each publish advice for owners ahead of storm season.
For tree owners
Storm tree scams: what attorneys general and trading standards warn owners about
After storms, state attorneys general in the United States and trading standards services in the United Kingdom publish warnings about tree trimming and removal offers.
Safety
Storm work: the hazards official guides warn about
After a big wind or ice storm the work piles up and the hazards change.
For tree owners
Tree touching power lines: who is responsible, country by country
When a tree touches or leans on a power line, the pages of regulators and utilities in each country say who clears it, who must be called and how far to stay back.
Roots near houses
For tree owners
Tree roots and buildings: what surveyors, a council and extension services say
The Royal Institution of Chartered Surveyors, an English borough council and two US university extension services explain how roots and buildings interact.
For tree owners
Tree roots in drains and sewer pipes: what a tree society, a city, a university and a council say
The International Society of Arboriculture, the City of Cleveland, the University of Tennessee and Merri-bek City Council in Victoria each write about roots in sewer and drain pipes.
Stump removal
For tree owners
Stump removal options: how three extension services describe them
Illinois Extension, South Dakota State University Extension and Colorado State University Extension each set out ways to deal with a tree stump.
Tree costs
For tree owners
Why tree work costs what it does: the factors the trade bodies and extension services name
Trade bodies, extension services, a safety regulator and a state attorney general name factors that change what a tree job involves and so what a quote covers.
DIY removal
For tree owners
Doing tree work yourself or hiring: what regulators and trade bodies say
Trade bodies, two workplace regulators and an extension service each say something to tree owners about doing tree work without a professional.
Renting equipment
For tree owners
Renting a stump grinder or chipper: what the regulators and extension services say
This page is about stump grinders and wood chippers.
Wildlife, bees and things in the tree
Law & permits
Birds, bats and the law: wildlife in the tree, country by country
What each country's wildlife agencies say about active nests, bat roosts and protected animals in trees that are being worked on, and who they say to call.
Choosing and growing trees
For tree owners
Choosing a tree to plant: what ISA and the Arboricultural Association tell owners
The International Society of Arboriculture and the Arboricultural Association each publish owner pages on picking a tree and a planting spot.
For tree owners
Pruning and topping: what the tree bodies tell owners
The International Society of Arboriculture and the Arboricultural Association publish leaflets for tree owners on pruning, timing and topping.
For tree owners
Trees on official invasive plant lists: what New York, Ohio and Pennsylvania say
New York, Ohio and Pennsylvania each publish a list of plants their rules treat as invasive or noxious.