Tree service research

Credentials first. ISA describes certification as "a nongovernmental, voluntary process by which individuals can document their base of knowledge" and notes it "demonstrates the individual has the minimum knowledge and skill requirements to perform work according to the scope of the program they hold a credential in." Two things follow: it belongs to a person, not a company, and it is a floor rather than a ceiling. Get the individual's name and search it. ISA also notes some certified arborists opt out of the public directory, so a miss is a question, not a verdict.

Licensing is a separate matter and it is state-specific. Some states license tree care contractors or require registration; many do not, and some regulate only pesticide application. Look up your state's contractor licensing board or department of agriculture and search the company name. Do not accept "licensed and insured" on a truck door as evidence of either.

Insurance is the check that actually protects your money, and it must come from the insurer. Ask for a certificate of insurance emailed directly by the company's agent, showing general liability and workers' compensation with current effective dates. A forwarded PDF from the contractor is not verification.

Then read reviews with a filter. Look for reviews that describe property damage, cleanup disputes and stump surprises — the failure modes specific to this trade — rather than counting stars. The Insurance Information Institute recommends checking the Better Business Bureau and requesting references before any financial commitment, and warns explicitly against being rushed into a contract.

How to choose

Search the arborist's name, not the company

ISA certification is an individual credential. Ask who holds it and verify that person in the public directory.

Insist the insurance certificate comes from the agent

Directly emailed, current dates, general liability and workers' compensation. This is the single most protective five minutes you will spend.

Check your state licensing board yourself

Requirements vary widely by state and some states do not license tree work at all. Find out what applies where you live rather than assuming.

Call two recent local references

Ask specifically about cleanup, lawn damage, the stump, and whether the final price matched the quote.

Read the one- and three-star reviews

Five-star reviews tell you the job went normally. The middle and low reviews tell you how the company behaves when it does not.