Arborist Report for a San Mateo County (unincorporated) Tree Permit
San Mateo County (unincorporated) requires an arborist report with every private-tree removal application. We write reports to San Mateo County (unincorporated)'s checklist, measured as San Mateo County Ordinance Code Title 8, Art. 7, Ch. 8.400 Protected Tree Ordinance, secs. 8.400.010-8.400.290 specifies.
What San Mateo County (unincorporated) requires
Required. Every Protected Tree Removal Permit and Protected Tree Pruning Permit application (8.400.120(2): 'An arborist report, consistent with this ordinance and its companion document'); the County application form (updated 04/21/2026) says 'Please refer to the Arborist Report Template for guidance on preparing a complete report' and sanmateocountytrees.org: 'Reports are required with a protected tree removal or protected tree pruning permit application'. NOT required for an Expedited Tree Removal Permit for the listed species (acacia, fruit/nut trees, tree of heaven, Italian cypress, eucalyptus, Monterey cypress outside the Coastal Zone, privet, sweetgum, tanoak, magnolia, myoporum, olive, pines, ornamental pear, pepper tree, bay laurel, palms except Canary Island date palm; max 3 trees per parcel per year), which needs photos only (8.400.130(2)). Emergency removals need a TRAQ arborist's written verification within 72 hours (8.400.230(2)). Dead-tree exemption rests on a certified/consulting arborist's determination (8.400.030(8)). Development applications need an Existing Tree Plan and Tree Protection Plan prepared by a certified arborist (8.400.170). The 8.400.120 list also allows the Director to require a licensed architect/engineer report where structural damage is claimed.
Who may write it: 'CERTIFIED OR CONSULTING ARBORIST' (8.400.030(5)): certified by the International Society of Arboriculture, a member of the American Society of Consulting Arborists, or an arboricultural professional approved by the Director of Planning and Building; 'ARBORIST REPORT means a professional report prepared by a certified arborist that meets the requirements outlined in the companion website' (8.400.030(1)). Hazard/emergency ratings must come from a Tree Risk Assessment Qualified (TRAQ) arborist.. None. County publishes an Arborist Report Template (sanmateocountytrees.org, County-of-San-Mateo-Arborist-Report-Template_2024.docx) and links the ISA and ASCA directories.
“Applications for Protected Tree Removal or Protected Tree Pruning permits shall include the following: 1. A completed tree removal or tree pruning application form provided by the Planning Department, signed by the property owner. 2. An arborist report, consistent with this ordinance and its companion document.” municipal code
The rule the report has to address
| Protected trees | Protected trees (8.400.060): (1) ANY species 12.1" diameter (38" circumference) or larger at 4.5 ft; (2) Protected Indigenous Trees per Table 1 at lower sizes: bigleaf maple, box elder, Pacific madrone, California buckeye, golden chinquapin, Oregon ash, Santa Cruz cypress, California sycamore, coast live oak, canyon live oak, blue oak, Shreve oak, black oak, valley oak, interior live oak and California nutmeg at 10"; Douglas fir and coast redwood at 18"; white/red alder and Fremont cottonwood 6" within riparian corridors; willows any size in riparian corridors and 6" trunks outside; Oregon white oak any size; (3) Board-designated Heritage Trees; (4) replacement trees and trees retained by a permit/development condition or enforcement action; (5) a 'community of trees' (five or more same-species indigenous trees over 6" DSH on one parcel, or an ecologically related group); (6) carbon-sequestration/mitigation trees. In the Emerald Lake Hills, Oak Knoll Manor, Palomar Park and Devonshire design review districts ANY tree 6" diameter (19" circumference) or larger is protected (8.400.070). RM and TPZ (and RM/CZ, PAD, TPZ/CZ outside the Midcoast urban area) parcels outside scenic corridors need no permit under this chapter (8.400.080-.090). Pruning permits: cuts 6" or larger on indigenous trees, any oak 30" DSH+ in urban areas, any heritage tree. |
|---|---|
| Size threshold | 12.1" DSH / 38" circumference (any species); indigenous species 10" (most), 18" (redwood, Douglas fir), 6" (riparian alder/cottonwood/willow), any size (Oregon white oak); 6" DSH / 19" circumference in Emerald Lake Hills, Oak Knoll Manor, Palomar Park and Devonshire DR districts; all at 4.5 ft (54") |
| Dead or hazardous trees | DEAD trees need no permit (8.400.100(8)); 'dead tree' = no longer alive or in advanced decline with less than 10% natural vigor 'as determined by a Certified or Consulting Arborist; or can otherwise be shown to be dead as determined by the Director of Planning and Building' (8.400.030(8)); County page: notifying Planning staff first is 'highly recommended'. EMERGENCY (8.400.230): a protected tree may be removed or severely pruned without a prior permit where it 'presents an imminent danger to life, property, utilities, or essential transportation systems, or a tree risk rating of High or Extreme is present, as assessed by an ISA Tree Risk Assessment Qualified Arborist (TRAQ)'; the owner must notify the Director (or the Sheriff after hours), photograph the tree, and within 72 hours submit photos and a TRAQ arborist's written verification; replacement trees are required; otherwise it is treated as a violation. Emergency Tree Removal Permit fee $221. FIRE-RISK SPECIES exemption (8.400.100(4)): eucalyptus, pines, acacia, tanoak and bay laurel with the trunk within 100 ft of any habitable structure (including neighbours') or 30 ft of an evacuation road need no permit unless 38" DSH or larger; defensible-space removals identified by CAL FIRE, the County Fire Marshal or local fire authority in High/Very High fire hazard zones are also exempt ((5)). Separate annual Director notice 'Permit Exemption for Hazardous Trees - Extended to July 1, 2027' (dated July 1, 2026) waives permits and fees for the same five species within 100 ft of a habitable structure or 30 ft of an emergency-evacuation road; the page is headed 'Only applicable to the Coastal Zone' (where the old Significant Tree Regulations still apply). Hazard trees not meeting the emergency test go through the normal permit with an arborist report; High/Extreme ratings need a TRAQ arborist's ISA Basic Tree Risk Assessment Form. |
| Permit fee | Planning Service Fee Schedule (updated 07/09/2026; Res. 080751 effective April 1, 2026, amended by Res. 082009 adopted June 23, 2026, effective July 23, 2026), 'Tree Permits': Protected Tree Removal Permit $444 per tree; Protected Tree Pruning Permit $331 per tree; Expedited Tree Removal Permit $221 per tree; Emergency Tree Removal Permit $221; Heritage Tree - New Designation $3,883; Appeal of Any Permit $2,021; violation fees charged at ten times the amount for tree cutting/trimming violations. In-lieu replacement fee $3,345 per tree not replaced on site (8.400.160(3)). CONFLICT: the County's Tree Trimming and Removal Permit web page still states 'Approximate Fee: Protected Tree (Removal: $670 / Pruning: $550), Expedited Removal: $430' (undated); the adopted schedule governs. Other department review fees (geotechnical, Public Works, Environmental Health, fire) may apply. |
| Penalty for removal without a permit | Table 3 (8.400.260) fines per tree by cumulative inches of DSH removed: first violation $1,500 (12-24" DSH) / $4,500 (25-48") / $7,500 (over 48"); second violation $4,500 / $10,500 / $18,000; third $7,500 / $15,000 / $22,500; served on the record owner and may also be served on the person doing the work; each tree is a separate infraction. Plus cease-work order, mitigation plan with new arborist report and replacement at the Director's discretion, stop-work on development until mitigation is installed and fees paid, a development moratorium of up to 18 months for violations outside development, a non-revocable maintenance bond, and a recorded notice of violation (8.400.250-.280). Fee schedule: violation permit fees at ten times the normal amount. |
| Department | San Mateo County Planning and Building Department, Current Planning Section, 455 County Center, 2nd Floor (Mail Drop PLN 122), Redwood City 94063; (650) 363-4161 (fee schedule and application form); Planning Desk (650) 363-1825; planningprojects@smcgov.org (applications may be emailed); online via Accela https://aca-prod.accela.com/smcgov; companion site https://sanmateocountytrees.org/ |
What the report contains
A signed PDF report. It states species and measurements taken the way the city's code requires, health and structural findings, and photographs. Where it matters, it gives a risk rating. The recommendation is written as the justification the city's code names, so staff can approve it without asking for more. For San Mateo County (unincorporated) that means measurements taken in diameter at 54″ above grade, the species identified against the city's protected list, the condition and structural findings, and the removal justification the code names, with replacement proposed as the code requires.
Price and turnaround
$750 to $1,250 for one to three trees, including the site visit, the findings the city requires and the replacement plan. Multi-parcel and development reports from $1,650. Responses to city comments $350 per round. Reports are delivered 7 to 10 business days after the site visit; responses to San Mateo County (unincorporated) comments are $350 per round unless the proposal includes one. Fees are confirmed in writing before the visit.
Full city rules: Tree permits in San Mateo County (unincorporated). Not sure the tree is protected? Run the permit checker.
Request a San Mateo County (unincorporated) arborist report
Questions about San Mateo County (unincorporated) reports
Does San Mateo County (unincorporated) accept a report from any arborist?
'CERTIFIED OR CONSULTING ARBORIST' (8.400.030(5)): certified by the International Society of Arboriculture, a member of the American Society of Consulting Arborists, or an arboricultural professional approved by the Director of Planning and Building; 'ARBORIST REPORT means a professional report prepared by a certified arborist that meets the requirements outlined in the companion website' (8.400.030(1)). Hazard/emergency ratings must come from a Tree Risk Assessment Qualified (TRAQ) arborist. None. County publishes an Arborist Report Template (sanmateocountytrees.org, County-of-San-Mateo-Arborist-Report-Template_2024.docx) and links the ISA and ASCA directories.
What if my tree is dead or dangerous?
DEAD trees need no permit (8.400.100(8)); 'dead tree' = no longer alive or in advanced decline with less than 10% natural vigor 'as determined by a Certified or Consulting Arborist; or can otherwise be shown to be dead as determined by the Director of Planning and Building' (8.400.030(8)); County page: notifying Planning staff first is 'highly recommended'. EMERGENCY (8.400.230): a protected tree may be removed or severely pruned without a prior permit where it 'presents an imminent danger to life, property, utilities, or essential transportation systems, or a tree risk rating of High or Extreme is present, as assessed by an ISA Tree Risk Assessment Qualified Arborist (TRAQ)'; the owner must notify the Director (or the Sheriff after hours), photograph the tree, and within 72 hours submit photos and a TRAQ arborist's written verification; replacement trees are required; otherwise it is treated as a violation. Emergency Tree Removal Permit fee $221. FIRE-RISK SPECIES exemption (8.400.100(4)): eucalyptus, pines, acacia, tanoak and bay laurel with the trunk within 100 ft of any habitable structure (including neighbours') or 30 ft of an evacuation road need no permit unless 38" DSH or larger; defensible-space removals identified by CAL FIRE, the County Fire Marshal or local fire authority in High/Very High fire hazard zones are also exempt ((5)). Separate annual Director notice 'Permit Exemption for Hazardous Trees - Extended to July 1, 2027' (dated July 1, 2026) waives permits and fees for the same five species within 100 ft of a habitable structure or 30 ft of an emergency-evacuation road; the page is headed 'Only applicable to the Coastal Zone' (where the old Significant Tree Regulations still apply). Hazard trees not meeting the emergency test go through the normal permit with an arborist report; High/Extreme ratings need a TRAQ arborist's ISA Basic Tree Risk Assessment Form.
How much is the San Mateo County (unincorporated) permit itself?
Planning Service Fee Schedule (updated 07/09/2026; Res. 080751 effective April 1, 2026, amended by Res. 082009 adopted June 23, 2026, effective July 23, 2026), 'Tree Permits': Protected Tree Removal Permit $444 per tree; Protected Tree Pruning Permit $331 per tree; Expedited Tree Removal Permit $221 per tree; Emergency Tree Removal Permit $221; Heritage Tree - New Designation $3,883; Appeal of Any Permit $2,021; violation fees charged at ten times the amount for tree cutting/trimming violations. In-lieu replacement fee $3,345 per tree not replaced on site (8.400.160(3)). CONFLICT: the County's Tree Trimming and Removal Permit web page still states 'Approximate Fee: Protected Tree (Removal: $670 / Pruning: $550), Expedited Removal: $430' (undated); the adopted schedule governs. Other department review fees (geotechnical, Public Works, Environmental Health, fire) may apply. The report fee is separate.