Palms near conductors: where the usual rules fit badly

A palm is vegetation, so GO 95 Table 1 and PRC 4293 apply at the same distances as for any tree. The provisions built on top fit badly: Rule 35 Exception 4 and 14 CCR 1257(a)(3) exempt trunks and major limbs, and a palm grows only from one bud at the top.

A Mexican fan palm stands eight feet to the side of a 12 kV lateral on a parkway strip inside Tier 2 of the High Fire-Threat District. Its frond tips are six feet below the lowest phase. The span owes 48 inches under Table 1, Case 14, the reading is 72, and the pre-inspector clears it. So far this is an ordinary parkway inspection.

The coast live oak across the street will lose the same margin to a growing season and get it back from a cut, and that cut can be repeated for as long as the tree stands. The palm has no equivalent cut. The tissue moving toward the conductor is the top of the plant, the only tissue that makes new growth is also the top of the plant, and a crew taking fronds off works underneath both.

Southern California Edison, reporting an inventory of about 80,000 palms in its 2021 Wildfire Mitigation Plan Update, puts the consequence in a parenthesis: the palm is "fast-growing (upwards)" and "may require multiple trims per year to maintain compliance."

The California stack has no palm exception. It has a palm problem, which is a different thing: the clearance duty lands squarely, and almost every relief valve attached to it is written around an anatomy a palm lacks.

The clearance duty attaches to vegetation, and a palm is vegetation

Rule 35 states the duty in a single clause:

the minimum clearances set forth in Table 1, Cases 13 and 14, measured between line conductors and vegetation under normal conditions, shall be maintained

The measured quantity is a distance from a conductor to vegetation. The sentence reaches every plant on the span, and Table 1 answers by voltage and location rather than by species.

PRC 4293 uses the same word on State Responsibility Area land, requiring clearance "in all directions between all vegetation and all conductors which are carrying electric current." The word itself goes undefined in both instruments. 14 CCR 1251 supplies the whole of Article 4's vocabulary in eight entries:

• conductor

• connector

• duff

• firebreak

• hot line tap or clamp connector

• outer circumference

• self-supporting aerial cable

• tree wire

Vegetation, tree, palm and frond are all absent from that list, so each of them means whatever a person in the field takes it to mean.

The palm on the parkway strip therefore owes 48 inches, exactly as the oak does. Which of the two rules supplies the number on a given span is the ordinary question, answered the ordinary way. The distance is set by the conductor and the case, and the species leaves it where it is.

The anatomy the rules name, and the anatomy a palm has

The divergence starts one level down, in the nouns. Every relief provision and every hazard duty in the stack identifies a part of a plant, and the parts they identify come from a broadleaf tree.

What the rule names	Where	What a palm has
Trunks and major limbs	GO 95 Rule 35, Exception 4	One unbranched trunk
The tree or limb, at the conductor level	14 CCR 1257(a)(3), criteria 1 and 2	Trunk only
Scaffold branches below 8.5 feet	14 CCR 1257(a)(3), criterion 3	None, at any height
Limbs and foliage of living trees	14 CCR 1254, 0 to 8 feet	Fronds, at crown height only
Dead, diseased or dying limbs and foliage	14 CCR 1254, above 8 feet	A skirt of dead fronds
Tree branches or foliage	GO 95 Table 1, Case 13 caption	Fronds

A frond is a leaf. ANSI A300 (Part 1)-2008, the pruning standard a trim specification would cite, says so in five words at clause 4.17: "A leaf structure of a palm."

The University of Florida's extension publication ENH1212 is equally direct about the rest of the structure. Palms "have no lateral meristems or vascular cambium," the tissues that in a dicot produce new wood and new bark each year. Aerial branching is routine in only a handful of genera, and a California distribution corridor is unlikely to carry one of them.

One practical consequence falls out immediately. Trunk diameter at a given point settles when that section of stem is formed and stays there. On the Mexican fan palm, UF/IFAS records a trunk tapering "from nearly 2 feet in diameter at the base to as little as 8 inches near the top," on a plant that reaches 70 to 100 feet. The eight inches at the top will still be eight inches in twenty years.

Growth runs one direction, and a trim does not run back

ENH1212 states the growth architecture in one sentence:

Palm stems are characterized by having a single apical meristem or growing point, which is also referred to as the bud or heart.

Everything follows from where that bud sits. New fronds emerge from the top of the stem, the stem lengthens beneath them, and the crown rises. A crew removing fronds removes tissue below the bud, so the operation that restores side clearance leaves vertical clearance where it was. The publication is equally plain about the alternative: "Death of the apical meristem in a palm results in the death of that stem in clustering species and death of the entire palm in single-stem species."

SCE's 2021 plan treats that boundary as an operational option, describing something the company intended to pilot with property owners: "extreme actions such as trimming deep enough to kill the palm when other alternatives are not available." Cutting to the bud is a removal performed with a saw and recorded as a trim, and a program that does it should say so in the file rather than leave a dead palm standing as a completed work order.

The arboricultural standard runs the other way for everything short of that. ANSI A300 (Part 1)-2008 clause 8.2 says live healthy fronds "should not be removed," and clause 8.3 makes the restriction binding above horizontal, with one exception: "Palms encroaching on electric supply lines."

Line clearance is the single reason the standard allows a live frond above horizontal to be cut. A specification calling for more than that has left the standard it cites, and the 2008 edition was revised in 2017, so the clause numbering in a current specification is worth checking against the edition in force.

Exception 4 and 14 CCR 1257(a)(3), tested on a palm

The two provisions that let vegetation stand closer than the tabulated distance are the ones a palm program reaches for, and both are drafted around limbs. Rule 35's fourth exception reads:

Mature trees whose trunks and major limbs are located more than six inches, but less than the clearance required by Table 1, Cases 13E and 14E, from primary distribution conductors are exempt from the minimum clearance requirement under this rule. The trunks and limbs to which this exemption applies shall only be those of sufficient strength and rigidity to prevent the trunk or limb from encroaching upon the six-inch minimum clearance under reasonably foreseeable local wind and weather conditions.

The exemption attaches to trunks and major limbs. A palm supplies one of those two, so at most the trunk is exempted, leaving the fronds outside the sentence. The fronds are the part actually approaching the conductor on the parkway strip. The rigidity test then asks about strength under foreseeable wind, which on a Mexican fan palm is a question about an eight-inch stem carrying a crown at 70 feet.

14 CCR 1257(a)(3) sets three criteria for an Exempt Tree on State Responsibility Area land, and each lands differently on a palm.

• Six inches or more from the line at all times. The criterion says "the tree or limb," and whether a frond is either is the open question. A frond that reaches inside six inches when the crown moves is the case the phrase "at all times" was written for.

• At least six inches in diameter at the conductor level. A Canary Island date palm clears this on a trunk UF/IFAS puts at 2 to 3 feet in diameter. A Mexican fan palm whose conductor-level section sits near the top of its taper clears it by about two inches, and because the stem holds its diameter, a section measuring five inches today measures five inches permanently.

• No scaffold branches below eight and one-half feet from the ground. A palm satisfies this by having no scaffold branches at any height, which is a different fact from the one the criterion was written to test.

Both provisions say who resolves the ambiguity, and they name different people. Rule 35's exception puts it on the company and then above it: "The utility shall bear the risk of determining whether this exemption applies, and the Commission shall have final authority to determine whether the exemption applies in any specific instance."

Section 1257(a)(3) hands the confirmation to "a Certified Arborist or a Registered Professional Forester," whose sign-off then carries annual inspection, a database row and a July 1 report to CAL FIRE. A palm claimed under either route needs a written determination naming the part that was measured, because the noun each rule supplies belongs to a different plant.

The dead frond skirt gets two different answers

A Washingtonia holds its spent fronds. The skirt hangs from the base of the crown down the stem, and the California Invasive Plant Council puts the reason it matters in seven words: "dead fronds of the tree can create a fire hazard." SCE's plan says the same thing with the wind added, calling dead fronds "highly flammable and easily blown long distances by winds."

Read that skirt against the two hazard duties and they diverge. Rule 35's second paragraph reaches it:

that dead, rotten or diseased trees or dead, rotten or diseased portions of otherwise healthy trees overhang or lean toward and may fall into a span of supply or communication lines, said trees or portions thereof should be removed

A frond skirt is a dead portion of an otherwise healthy tree, which is the category the sentence names. Two conditions govern whether the duty runs: the company must have actual knowledge, and the portion must overhang or lean toward a span. The verb is "should."

The felling sentence in PRC 4293 reaches a different set of trees, and it lists four of them:

• "Dead trees"

• "old decadent or rotten trees"

• "trees weakened by decay or disease"

• "trees or portions thereof that are leaning toward the line"

Those "shall be felled, cut, or trimmed so as to remove such hazard." A vertical living palm sits outside all four. It is alive, sound, free of decay, and standing straight. So the statute's mandatory verb attaches to conditions the plant fails to meet, while the General Order's permissive verb attaches to one it satisfies. On a single State Responsibility Area span the same skirt is a Rule 35 finding and a PRC 4293 silence, and the two get filed in different units against different agencies.

Note the question both duties skip. The hazard tree assessment begins with whether the tree can reach the conductor if it fails, and it is built around structural failure of a stem or a limb. A palm dropping a frond has not failed structurally. It has shed a leaf on schedule.

Inside the pole firebreak the skirt is not a judgment call

PRC 4292 requires a 10-foot firebreak around a subject pole, and 14 CCR 1254 turns that into a cylinder with three vertical bands. Two of them bite on a palm, and they bite in opposite directions.

Above eight feet, the regulation requires a crew to "remove dead, diseased or dying limbs and foliage from living sound trees." A frond skirt is dead foliage on a living sound plant. Inside the cylinder the discretion Rule 35's "should" leaves open disappears, and the skirt comes out.

From ground level to eight feet, the regulation requires that "all limbs and foliage of living trees shall be removed up to a height of 2.4 m (8 feet)." On a seven-foot palm growing four feet from a fused riser pole, all of the foliage is the whole crown, and removing the whole crown removes the bud. Complying with the firebreak rule as written kills that palm.

Article 4 leaves open whether a palm counts as a "living tree" for the purposes of that sentence, and on State Responsibility Area land the reading that matters in the moment belongs to the CAL FIRE inspector. The workable answer is to take the palm out as a planned removal and record it as one, rather than reach the same outcome through a clearing order and explain it afterward.

A frond in the air is outside every clearance number

Every distance in the stack runs from a conductor to vegetation rooted where it stands. That is what makes a clearance measurable, and it is what a LiDAR return or a tape at the base of the span captures.

A detached frond has no such distance. UF/IFAS describes the Canary Island date palm as carrying "8- to 15-foot-long rigid leaves." Once one of those is off the plant and moving in a wind event, there is no pair of endpoints to put a tape between.

SCE's plan describes fronds that "drop onto primary wire" as a major driver of emergent work and outages, and lists "frond drop" as a risk attribute of at-risk species, in the same sentence as trunk failure, branch failure, limb sway, root failure and flammability. Five of those six are structural failures of a plant that then intersects a conductor. Frond drop is the routine behavior of a healthy one.

The compliance consequence is narrow and worth stating plainly. A span can pass its Case 14 reading on the day of inspection, pass it again on the next cycle, and still appear in the vegetation-caused outage count or in the ignition report's vegetation field because of the palm at its edge. A clearance record is evidence about a distance. It says nothing about causation, and a program treating the two as interchangeable will be surprised by its own data.

What a palm does to the cycle

GO 95 Appendix E is where species enters the regulation, and it enters as a permission. The appendix lists factors a utility "may" weigh in setting clearances beyond the recommended figures, among them "species type, experience with particular species, vegetation growth rate and characteristics." Species, rate and interval are all left to the utility. The cycle is the utility's own number, committed in the wildfire mitigation plan.

So the arithmetic belongs to the program, and on a palm three of its terms behave unusually. The approach to the conductor is vertical, so the margin a trim buys is the margin that existed before the trim. The rate holds steady as the plant matures. And the cost per visit is set by access: SCE reports that "approximately 40% of palm inventory requires climbing the tree to trim it," against a fleet that is otherwise worked from a bucket.

Run those together and the filed answer is the one SCE gives, that palms "may require multiple trims per year to maintain compliance," which functions as a standing commitment to revisit rather than as a cycle. The alternative the same plan reaches for is removal, and the same paragraph records why it moves slowly: "customers have proven to be very resistant to removals."

That resistance is where the compliance file starts to matter more than the cycle. A refused palm on a parkway strip runs into Exception 2's good faith effort.

On State Responsibility Area or High Fire-Threat District land it also runs into PRC 4295.5's entry right, which authorizes pruning for clearance work and authorizes removal only for hazardous, dead, rotten, diseased or structurally defective trees. A healthy palm that is simply too close falls outside that list. Pruning is the one remedy the section authorizes for it, and pruning is the remedy that wears off.

What the record has to name

Everything above leaves the numbers alone. All of it changes what a file has to say for a number to be testable two years later, and every item below is something an auditor can request by name.

Which part of the plant the measurement ran to. Frond tip, frond base, or trunk. On any palm claimed under Rule 35 Exception 4 or 14 CCR 1257(a)(3), both the trunk distance and the frond distance, because the exemption language reaches one of them and the hazard is the other.

The vertical margin, separately from the radial one. The distance from the crown to the conductor above it, dated. That single figure is what the next visit is scheduled against, and it is the one a trim leaves untouched.

Whether the work was a frond removal or a removal of the palm. Including the case where the cut reached the bud. A dead standing palm closed out as a trim is a record that disagrees with the site.

The skirt, as its own observation. Present or removed, and under which instrument: Rule 35's actual-knowledge paragraph, or the 14 CCR 1254 band that applies within 10 feet of a subject pole.

The determination, and who signed it, for any exemption claimed. Rule 35 Exception 4 puts the risk on the utility and leaves the Commission the last word, so the file needs the reasoning as well as the conclusion. A 14 CCR 1257(a)(3) claim needs the Certified Arborist or Registered Professional Forester by name, the three measurements, and the database row that follows.

One absence is worth knowing about before an inspection. CAL FIRE's 2021 California Power Line Fire Prevention Field Guide, the document an agency inspector works from, runs to 138 pages and contains no occurrence of the words palm or frond. There is no published state guidance on how any of these provisions read on a palm. Until there is, the determination belongs to the utility, made in writing, tree by tree, and the file is the only place it exists.

Further reading

• GO 95 Rule 35: what the vegetation rule requires: The rule this page applies to a plant it was not drafted for, including the four exceptions and the actual-knowledge trigger.

• 14 CCR 1257: which trees are exempt, and the records that prove it: The Exempt Tree criteria, the annual inspection and the July 1 report a palm claim would have to carry.

• Species growth rate and how it sets the trim cycle: The equation a palm breaks, because its rate of approach runs vertically and no cut resets it.

Frequently asked questions

Does GO 95 Rule 35 apply to palm trees?

Yes. Rule 35 requires the Table 1, Cases 13 and 14 clearances measured between line conductors and vegetation, and it names no species. A palm beside a 12 kV lateral owes 18 inches under Case 13 and 48 inches under Case 14, the same figures an oak in the same position owes.

Can a palm qualify for Rule 35 Exception 4 or as an Exempt Tree under 14 CCR 1257?

Both provisions are drafted around trunks and major limbs, and a palm has an unbranched trunk and no limbs. The trunk can be measured against the six-inch tests, and 14 CCR 1257(a)(3)'s scaffold branch criterion is satisfied by a plant that has no scaffold branches at any height. Neither provision says what to do about fronds. Rule 35 Exception 4 puts the risk of the determination on the utility and gives the Commission final authority, and 14 CCR 1257(a)(3) requires confirmation by a Certified Arborist or a Registered Professional Forester.

Why can a palm not be trimmed back to restore clearance?

Palms have a single apical meristem at the top of the stem, no lateral meristems and no vascular cambium. Height comes from that one bud, so removing fronds below it does not lower the crown, and cutting to the bud kills the palm. Southern California Edison's 2021 Wildfire Mitigation Plan Update describes trimming deep enough to kill the palm as an extreme action to be considered when other alternatives are not available.

Does a dead palm frond skirt have to be removed?

It depends on which rule is asked. Under GO 95 Rule 35 a skirt is a dead portion of an otherwise healthy tree, and where it overhangs a span and the company has actual knowledge of it, the rule says it should be removed. PRC 4293's felling sentence reaches dead trees, old decadent or rotten trees, trees weakened by decay or disease, and trees or portions leaning toward the line, and a vertical living palm is in none of those categories. Within 10 feet of a PRC 4292 subject pole, 14 CCR 1254 requires dead foliage to be removed from living sound trees above 8 feet, which is not discretionary.