Our Commitment
Urban Forestry Guide is an independent resource built by a practicing ISA Certified Arborist. Our purpose is to help Peninsula homeowners find qualified, trustworthy tree care — evaluated against the same professional standards used in the arboriculture industry.
We believe homeowners deserve better than star ratings and paid ads. They deserve evaluations from someone who understands tree biology, proper pruning, structural integrity, and what separates a qualified arborist from someone with a truck and a chainsaw.
TL;DR
No pay-to-rank: Companies can't pay for placement or better scores.
How we're paid: Consulting fees and (sometimes) referral fees if you request quotes through this site.
What rankings mean: A snapshot of compliance + credential signals at the time of review — not a guarantee of outcome or price.
On This Page
How We Evaluate Companies
Every tree service featured on this site is evaluated against five categories based on ISA professional standards, industry best practices, and verifiable public information. Companies cannot pay for higher scores or better placement in our editorial rankings.
| Category | Weight | What We Evaluate |
|---|---|---|
| Verification & Compliance | 30% | Active contractor license, general liability insurance, workers' compensation, business registration, and clear safety practices (e.g., documented training, PPE, and jobsite controls when available). |
| Arborist Professionalism | 20% | ISA Certified Arborists on staff, TRAQ qualifications, adherence to ANSI A300 pruning standards, proper pruning language in marketing and communications. |
| Scope & Communication | 20% | Provides written scopes of work before starting, includes photos and clear descriptions, demonstrates permit awareness, communicates timeline and process. |
| Reputation & Track Record | 15% | Pattern of reviews (not just star average), recency and consistency, how complaints are handled, tenure in the community. |
| Responsiveness | 15% | Response time to inquiries, punctuality, follow-through on commitments, clarity of customer communication. |
What We Verify
- Active California contractor license (CSLB lookup)
- General liability insurance (current certificate)
- Workers' compensation coverage (or valid exemption — if a company uses subcontractors or has employees, workers' comp is typically required)
- ISA certification status (ISA credential lookup)
- No evidence of topping promoted as routine service
- Business registration and physical presence in service area
Automatic Disqualifiers
Companies exhibiting any of the following are not featured on this site:
- No valid contractor license or expired license
- No general liability insurance
- Advertising tree topping as a routine pruning service (note: we distinguish between improper topping — indiscriminate cutting of main stems — and legitimate crown reduction pruning performed to ANSI A300 standards)
- Operating without workers' compensation in situations where coverage is typically required (e.g., employees or subcontracted crews)
- Pattern of unresolved complaints or deceptive practices
- Door-to-door solicitation after storms (common predatory practice)
- Demands cash-only payment or large deposit upfront before providing a written scope of work
Compensation & Business Model Disclosure
Disclosure & Editorial Independence
How we make money: (1) Paid arborist consulting — independent tree evaluations, risk assessments, and written reports ( learn more ), and (2) referral fees from providers when homeowners request quotes through this site.
We may receive a referral fee from a provider if you choose to request quotes through this site. You are never required to hire anyone we introduce, and you can always contact any company directly.
No pay-to-rank: Companies cannot pay for higher placement, improved scores, or inclusion in editorial rankings.
How we prevent bias: Rankings are determined using the rubric on this page and are completed before any referral is made. The scoring process is not adjusted based on referral participation. If we ever offer sponsored placements, they will be clearly labeled and separated from editorial content.
How We Handle Conflicts of Interest
As an arborist consultant who also recommends tree services, we recognize the potential for conflicts of interest. Here's how we manage them:
- Scoring is completed before any referral is made, and rankings are not adjusted based on referral participation
- Our evaluation rubric is published and transparent — anyone can see how scores are calculated
- We evaluate companies we refer to using the same standards as companies we don't
- We will never recommend unnecessary work to generate referral revenue
- If our consulting assessment finds no work is needed, we'll tell you that — even though it means no referral
- Companies can request a re-evaluation at any time if they believe their score doesn't reflect improvements
What Our Rankings Are (and Aren't)
Our rankings reflect compliance signals, credentials, scope quality, and reputation patterns at the time of review. They are not a guarantee of outcomes, pricing, or availability. Homeowners should still request written scopes, confirm insurance, and compare bids before hiring.
We recommend verifying license status via CSLB and confirming insurance directly with the provider. Information can change at any time.
Keeping Information Current
Tree service quality changes over time. A company that was excellent two years ago may have different staff, ownership, or practices today. We address this by:
- Re-evaluating featured companies at least annually
- Displaying "Last reviewed" dates on all company evaluations
- Monitoring review patterns for significant changes
- Verifying license and insurance status at least quarterly
- Removing companies that no longer meet our standards
Open Data Sources
City-specific tree data on this site comes from publicly available municipal open data portals. These are government datasets published for public use. We do not scrape or collect private data. Sources include:
- San Francisco DataSF — Street Tree List and Urban Tree Canopy datasets
- City of Palo Alto Open GIS — public tree inventory
- San Mateo County Open Data — county GIS portal
- USDA Forest Service i-Tree Tools — ecosystem service calculations
Raw data is enriched with professional context by an ISA Certified Arborist, including species-specific care requirements, common diseases, and pruning recommendations relevant to the Peninsula climate.
Corrections & Updates
If you believe any listing is inaccurate — license status, credentials, insurance, ownership — contact us and we will investigate. Verified corrections are updated promptly, and we may re-score companies when material facts change.
Contact Us
If you're a tree service company and believe your evaluation doesn't reflect your current practices, or if you're a homeowner with feedback on our methodology, we want to hear from you.
Call (415) 881-0124 or request vetted quotes .
Last updated: March 20, 2026