ISA Certified Arborist Services in the Willamette Valley & Portland Metro

Not every tree problem requires removal. Santiam Tree Service employs an ISA Certified Arborist (PN-10032A) who provides expert assessments, science-based care plans, and independent consulting to help your trees and your property thrive for decades.

What Is an ISA Certified Arborist?

An arborist is a trained specialist in the care and management of individual trees. An ISA Certified Arborist has passed a rigorous examination administered by the International Society of Arboriculture (ISA) and maintains ongoing education to stay current with best practices in tree biology, risk assessment, and urban forestry.

At Santiam Tree Service, our ISA Certified Arborist is also ISA Tree Risk Assessment Qualified (TRAQ), a specialized credential that enables formal evaluation of tree structural failure risk. This means when we give you an expert opinion, it is backed by the most current science in the field.

Why does certification matter? Anyone can call themselves a “tree expert.” ISA Certification means the arborist has demonstrated verified competency in tree biology, pruning standards, diagnosis, and risk evaluation, the same standards used by municipalities, insurance companies, and courts when evaluating tree-related claims.

Our Certified Arborist Services

Science-based guidance for tree health, risk, preservation, and documentation across the Willamette Valley and Portland Metro.

Tree Health Assessment

Evaluation of structural integrity, root zone health, canopy condition, and disease or pest pressure before problems become emergencies.

ISA Tree Risk Assessment (TRAQ)

Formal assessment of failure likelihood, targets, consequences, and recommended actions in a written report.

Pest & Disease Diagnosis

Diagnosis for Oregon tree threats including sudden oak death, Swiss needle cast, bark beetles, and root rot.

Tree Care & Preservation Plans

Practical care plans for heritage trees, mature oaks, landscape trees, and root zones near construction.

Pre-Construction Tree Consulting

Tree protection zones, grading-plan review, and contractor specifications to reduce construction-related tree decline.

Expert Witness & Written Reports

Professional documentation for disputes, property sales, insurance claims, permits, and formal opinions.

Our Arborist Consultation Process

A clear visit, plain-language findings, and an action plan built around the right outcome for your property.

Step 01

Schedule Consultation

Contact us to arrange an on-site visit focused on diagnosis, evaluation, and planning, not just pricing a job.
Step 02

On-Site Evaluation

Our certified arborist examines the tree or trees, then gathers data on species, structure, soil environment, and surrounding targets.
Step 03

Assessment & Findings

We explain what we observed, what it means for tree health and safety, and what options you have. Formal assessments include a written report.
Step 04

Action Plan

Whether the recommendation is monitoring, pruning, treatment, cabling, or removal, we lay out honest options without unnecessary upselling.

Credentials That Matter

Our ISA Certified Arborist holds current credentials for professional tree care, formal risk evaluation, and trusted documentation.

ISA Certified Arborist

PN-10032A credentialed by the International Society of Arboriculture, with verified competency in tree biology, pruning standards, diagnosis, and risk evaluation.

Tree Risk Assessment Qualified

TRAQ qualification is the gold standard for formal tree failure risk evaluation, including likelihood of failure, targets, consequences, and recommended action.

Santiam Tree Service is fully licensed, bonded, and insured: CCB #229652 | WA #SANTITS7590W.

Frequently Asked Questions

What's the difference between an arborist and a tree trimmer?

A tree trimmer removes branches to improve appearance or clear hazards. An ISA Certified Arborist is a trained diagnostician – they evaluate tree health, assess structural risk, diagnose disease, and develop care plans based on tree biology. Think of the difference as a barber versus a physician. Both work with the same subject, but the skill set, scope, and accountability are fundamentally different.

In many cases, yes. Cities like Portland, Lake Oswego, and Salem require a formal arborist assessment before issuing permits to remove or significantly modify certain protected trees. Our certified arborist can provide the documentation your city requires. Requirements vary by municipality, so we recommend contacting us to confirm what applies to your property.

Common warning signs include sudden or progressive leaning, large dead limbs, cracks or splits in the main trunk or major limbs, fungal growth at the base indicating root rot, or a history of storm damage. However, many structural defects are not visible from the ground – which is why a formal ISA Tree Risk Assessment is the most reliable way to evaluate risk.

Often, yes. Removal is not always the right answer. Structural cabling, targeted pruning, soil remediation, or disease treatment can extend the life of a valuable tree significantly. Our arborist will give you an honest assessment of whether a tree can be saved and what it would take – so you can make an informed decision.

Yes. Our ISA Certified Arborist serves both the Willamette Valley, including Albany, Salem, Corvallis, Lebanon, Eugene, and surrounding areas, and the Portland Metro, including Portland, Lake Oswego, Tigard, Tualatin, Oregon City, Wilsonville, Canby, and more.

A formal TRAQ assessment report documents the tree species, location, observed defects, likelihood of failure, size of the part likely to fail, potential targets, and an overall risk rating: low, moderate, high, or extreme. It includes recommended actions and a re-inspection interval. This document is recognized by insurance companies, municipalities, and courts.

Get an Expert Opinion on Your Trees.

Whether you need a formal risk assessment, a tree health evaluation, or just want a certified expert’s opinion before making a decision, we’re here to help. Serving the Willamette Valley and Portland Metro – call us or request a consultation online.