Understanding the utility's pre-inspection and arborist assessment

The pre-inspection is the visit where the decision about a tree is made, and the person making it is usually an ISA Certified Arborist. ISA states that credential is not a license and that no other conclusions may be drawn from it. PG&E names Certified Arborist with TRAQ for one work category only.

A pickup stops on the shoulder below a 12 kV distribution span at 9:40 on a Tuesday. Someone gets out with a tablet and a can of spray paint, walks about sixty feet up the drive, stands under a valley oak for four minutes, sprays a mark near the base, types for a minute, and leaves. Nobody knocks.

Six weeks later the answer to a phone call is that an arborist assessed the tree.

Both halves of that sentence carry more than they look like carrying. The assessment was four minutes long and it decided what happens to the tree. The word arborist names a credential with an expiration date and a public register. This is what each one is.

The visit is where the decision gets made

The utility's word for this trip is pre-inspection, because it comes before the work. ACRT Pacific, one of the contractors that staffs the role in California, describes the job in a sentence:

Our arborists examine circuits for hazard trees, encroachment, and potential encroachment, as well as evaluate clearances.

PG&E states the scope for property owners more plainly on its Trees and Powerlines page:

Inspectors check for vegetation that creates a safety risk or causes a power outage.

Everything downstream follows from those four minutes. The shape sprayed on the trunk, whether a crew comes at all, how much wood comes off, and whether the tree is still standing in the fall were all settled while the inspector was typing. What the inspection produces, field by field, lives in the utility's system of record, and the crew that arrives months later is executing it rather than deciding it.

That is the practical reason to care who the person on the shoulder was. It is the only visit at which the outcome is still open.

The credential behind the word is an exam with published weights

The credential the industry means by arborist is the ISA Certified Arborist, issued by the International Society of Arboriculture. Its program guide, revised August 2025, sets eligibility first:

The ISA Credentialing Council requires a candidate to have a minimum of three years of full-time experience in arboriculture or a combination of education and practical arboricultural experience. One year of full-time experience is equal to approximately 1,795 hours of work.

A degree shortens that. A four-year bachelor degree with at least four arboriculture courses plus one year of practical experience qualifies, and a two-year associate degree with two such courses plus two years does the same.

The exam is 200 multiple-choice questions over 3.5 hours, 20 of them unscored pretest items, passed at 76 percent. The guide publishes how the questions are distributed across ten areas of knowledge.

Area of knowledge	Share of the exam
Safe Work Practices	15%
Pruning	14%
Tree Biology	11%
Tree Risk	11%
Tree Identification and Selection	9%
Installation and Establishment	9%
Diagnosis and Treatment	9%
Trees and Construction	9%
Soil Management	7%
Urban Forestry	6%

Tree Risk is 11 percent of it. The credential is a general arboriculture credential that covers the whole trade, and the part of the trade that bears on whether your oak can reach a conductor is about one question in nine.

ISA prints the ceiling on its own credential

This is the paragraph worth reading before the word arborist does any persuading. It is ISA's, about ISA's own program:

By passing the exam, holders of ISA certifications have demonstrated an internationally accepted fundamental level of knowledge and skills in the area in which they are certified. No other conclusions may be drawn concerning certification holders. ISA certifications do not represent licensure, registration, or other authorization to practice or to conduct business activities for a fee or otherwise.

The certification is not a license. It is a passed exam plus verified experience, maintained on a clock, from a body accredited to ISO/IEC 17024. What California licenses is the business rather than the person, and the classification that covers planting, maintaining and removing trees is C-49. Neither instrument makes the holder an authority whose reading of your tree is final, and neither is meant to.

The utility version is a second exam

There is a credential built for exactly the conversation happening in your driveway, and it is the ISA Certified Arborist Utility Specialist. ISA describes it in one line:

This certification is for current ISA Certified Arborists who already work in utility vegetation management.

The general credential is a prerequisite, so the Utility Specialist sits on top of it. Eligibility then needs one of three experience records.

• 2,000 hours of direct electric utility vegetation management experience over the past two years.

• 36 cumulative months in the last ten years employed full time as an electric utility arborist, forester or vegetation manager.

• 36 cumulative months in the past ten years on a project as a utility vegetation management contract employee or consultant.

What the second exam covers is the tell:

You will be tested on topics such as electric utility pruning, program management, integrated vegetation management, electrical knowledge, customer relations, and storm response.

Customer relations appears on that list and appears nowhere in the ten areas of the general exam. The conversation at your gate is a tested subject on one credential and not on the other.

Which credential your inspection actually required

PG&E's Utility Procedure TD-7102P-01, Vegetation Management Distribution Inspection, Revision 4, effective November 15, 2025, sorts distribution inspection work into two categories. Table 2 gives the Elevated one a qualification line:

Assessment Type: Includes the components of the Standard work category AND Level 2 Inspections of all Strike Trees Minimum Qualifications: Certified Arborist-Tree Risk Assessment Qualification (TRAQ)

The Standard row above it carries an assessment type and a focus and no Minimum Qualifications line at all. Two credentials stacked are named for one category and nothing is named for the other. What the TRAQ qualification proves, and what it leaves open, is a narrower thing than a roster suggests.

Which category covered your span was fixed before the truck left the yard. Step 1.3 puts it in the preparation, where the inspector identifies the work assignment as a Routine Patrol or a Hazard Patrol, each of which may run Standard or Elevated. Nobody standing on your driveway chooses it.

The procedure's own training requirement is one sentence, under Before You Start:

All VMIs must complete PG&E Academy trainings required for inspections prior to performing this procedure.

That points at an internal course catalog rather than at a credential, and the document itself carries a Level of Use of Informational Use. What actually binds a contractor running a pre-inspection cycle is the contract rather than the procedure, and that contract is not public. Where the requirement lands is a decision PG&E makes in its own paperwork, not one a state rule settles.

Who the person is likely to be

Two different jobs get described with the same word on a property, and the payroll tells them apart.

PG&E and IBEW Local 1245 created the utility's own inspector classification in Letter Agreement LA R1 20-02-PGE, dated June 23, 2020. It established Vegetation Management Inspector, SAP code 52435198, at a 2019 wage rate of $39.00 for the first six months and $42.19 after. The job description has that person overseeing contractor crews, sitting in tailboard meetings, and authorized to suspend contractor work.

The pre-inspector shows up in that agreement as somebody else. One of the five ways to qualify for the PG&E classification is:

Five (5) years of experience as a Vegetation Management Pre-Inspector and Certified Arborist

Pre-inspection is the prior job, and in California it is usually a contractor's employee doing it. After placement, the PG&E inspector then has six months from the start date to pass an OSHA 30-hour construction safety overview, and six months from test eligibility to obtain the Certified Tree Safety Professional credential.

So the person who marked your tree is likely a contractor's certified arborist, and the PG&E employee wearing the same job family arrives later to watch the crew. What either of them is authorized to do on your property comes from the utility rather than from the credential.

You can check the number

ISA runs a public register. The directory sits at certificates.directory.isa-arbor.com, reached from ISA's consumer site, and ISA describes it as

designed to help the public, employers, and industry stakeholders easily find and verify ISA-credentialed tree care professionals.

It searches by name, by location or by ISA certification number, and ISA states it is strictly intended for verifying or locating credential holders in order to secure tree care services.

The reason to use it is the clock. An ISA Certified Arborist credential is valid for three years. Retaining it means retaking the exam or accumulating at least 30 continuing education units across the three years in the ten tested domains and paying a $220 recertification fee. Lapsed is a real state, and the register is where it shows.

A certification number on a card, a name, and one search is the whole procedure. It takes less time than the inspection did.

The code the credential carries, and what it does not reach

The certification comes with an enforceable code, and ISA says so in the Code of Ethics itself:

Regardless of any other professional affiliation, this ISA Code of Ethics applies to those individuals seeking ISA certification (candidates), and all individuals certified by the ISA as (credential holders). The ISA Code of Ethics establishes appropriate and enforceable professional conduct standards, and explains the minimal ethical behavior requirements for credential holders and candidates.

Three clauses of it land in a driveway conversation.

• II.A.2 requires the holder to "[r]ecognize the limitations of their professional ability and provide services only when qualified," and makes the holder responsible for determining those limits.

• II.A.3 requires "a reasonable effort to provide appropriate professional referrals when unable to provide competent professional assistance."

• II.B.1 requires disclosure to clients or employers of "significant circumstances that could be construed as a potential or real conflict of interest or an appearance of impropriety."

Read together they say what the inspector owes you at the gate: an honest account of what the assessment did and did not look at, and a referral where the question is outside it. They say nothing about the prescription. The code binds the person; the decision about the tree belongs to the utility, and changing it runs through the utility.

The assessment was made from the conductor's side

This is the mismatch behind most complaints about a pre-inspection. The landowner expects an opinion about a tree. The inspector produced a judgment about a tree's relationship to a wire over a defined period.

A healthy valley oak growing steadily toward a 12 kV primary gets work prescribed, because the growth will close the required distance before the next cycle. A declining oak with a hollow trunk fifty feet clear of any conductor gets nothing written about it, because it is not the program's tree.

Nothing in the procedure asks the inspector to mention it, and no form exists for saying so. Whether that tree is a hazard tree in the sense CAL FIRE's field guide uses is a separate question from whether it is within reach of the line.

The two outcomes the inspection can write are pruning and removal. The criteria that choose between them are the utility's own, on one page of a procedure, and the shape sprayed on the trunk is how the decision is communicated to the crew.

An assessment that belongs to you is a separate transaction

Nothing from the pre-inspection is addressed to the property owner. The prescription goes into the utility's system of record, the mark goes on the trunk, and a door hanger may or may not go on the door. PG&E takes tree safety questions at treesafety@pge.com and 1-800-564-5080. SDG&E makes a narrower promise in its own territory, saying that an inspector or crew needing to reach a tree on private land "will provide advance notification, usually in the form of a phone call" or a door notice.

If you want a written opinion about a tree you own, you buy one. Ask whoever you hire to put the tree risk assessment level on the page, because the level is what determines how much of the tree was actually examined, and an assessment with no stated level cannot be compared to anything.

One limit applies to every arborist you might hire. California Penal Code section 385(b) makes it a misdemeanor to operate, place, erect or move tools, machinery, equipment, material, a building or a structure within six feet of a high voltage overhead conductor. Work inside that space takes a line-clearance qualification that most residential tree services do not hold, which is why the shape the utility left on the wire side of the tree is not something a second contractor can tidy up.

Five questions worth asking while the inspector is still there

The visit is short and the window closes when the truck pulls away. These are the ones with answers.

1. What is the prescription on this tree, pruning or removal, and what reason went into the record with it? 2. Is this circuit being walked as a Standard or an Elevated assignment? 3. Are you an ISA Certified Arborist, and what is your certification number? 4. Which company employs you, and who is the utility representative above you on this circuit? 5. When is the crew scheduled, and what will be left on the ground when they finish?

The third one is checkable in a minute. The first two determine everything that happens to the tree, and they are being written down while you stand there.

Further reading

• What to expect during a utility line-clearance visit: The three trips this visit is the first of, and who authors each one.

• Why did the utility mark or tag my tree: The paint the inspector leaves behind, and what each shape commits the tree to.

• Field hazard tree assessment: the level, the trigger, and the call: What a Level 1, a Level 2 and a Level 3 assessment each buy, and who schedules them.

Frequently asked questions

The utility told me an arborist assessed my tree. What does that certification actually mean?

Most often it means the ISA Certified Arborist credential. Eligibility is three years of full-time arboricultural experience, or a degree plus one or two years, and the exam is 200 multiple-choice questions in 3.5 hours passed at 76 percent. The ISA Certified Arborist Program Guide, revised August 2025, is blunt about the ceiling: "By passing the exam, holders of ISA certifications have demonstrated an internationally accepted fundamental level of knowledge and skills in the area in which they are certified. No other conclusions may be drawn concerning certification holders." Tree Risk is 11 percent of that exam.

Can I check whether the person who marked my tree is certified?

Yes, and it takes one search. ISA runs a public credential directory at certificates.directory.isa-arbor.com that finds a holder by name, by location or by ISA certification number, and ISA says it is "designed to help the public, employers, and industry stakeholders easily find and verify ISA-credentialed tree care professionals." The credential runs three years, so a lapsed one is a real result rather than a search failure.

Is an ISA Certified Arborist licensed by California?

The certification is not a license. ISA's own program guide states that ISA certifications "do not represent licensure, registration, or other authorization to practice or to conduct business activities for a fee or otherwise." California licenses the company rather than the person, through the Contractors State License Board, and the classification that covers planting, maintaining and removing trees is C-49.

Why did the inspector not tell me anything about my tree's health?

Because that is not what the visit assesses. PG&E's Trees and Powerlines page states the scope in one line: "Inspectors check for vegetation that creates a safety risk or causes a power outage." A healthy tree growing toward the conductor gets work prescribed. A declining tree far enough from the line to be nobody's safety risk gets nothing, and the inspector is under no procedure that requires mentioning it.

Can I get a copy of what the inspector wrote about my tree?

There is no form handed over at the gate. The prescription goes into the utility's system of record at the time of the inspection, and the artifacts that reach you are the mark on the trunk and, sometimes, a door hanger. PG&E takes tree safety questions at treesafety@pge.com and 1-800-564-5080, and the useful question is which prescription the vegetation point carries and when the work is scheduled.