Case 2: Georgetown Multi-Stem Heritage Pecan (27 in DBH)

STATUS: OA-RCA-v2:GTN-CI-204 | drafts complete: 1/1 | unverified citations: 0

# LEO-RCA Profile 01 Evidentiary Stewardship Brief (GTN-CI-204)

## Slot 1: Epistemic Status & Workstream Header
- **Workstream ID:** `OA-RCA-v2:GTN-CI-204`
- **Schema & Profile:** `RCA_v2` / `LEO-RCA-Profile-01`
- **Declared Epistemic Gaps:** `0`

## Slot 2: Sovereign Airlock & Fiduciary Boundary
- **Local Execution Airlock:** Computed deterministically in zero-dependency ECMAScript Modules with zero cloud runtime telemetry.
- **Fiduciary Separation:** Diagnostic biomechanics are decoupled from timber removal bidding. Municipal permit applications and site work require direct owner and credentialed arborist sign-off.

## Slot 3: Point-of-Use Resolution
- **Subject Specimen:** *Carya illinoinensis* (Pecan), tag `GTN-CI-204`
- **Geospatial Anchor:** Plus Code `8624J8MC+8Q` (Lat `30.63`, Lng `-97.68`)
- **Governing Municipal Code:** Georgetown Unified Development Code (UDC) Chapter 8 (Tree Preservation, Landscaping, and Fencing) (Georgetown, TX (tx-georgetown))
- **Point-of-Use Terms:** `DBH` = Diameter at Breast Height (4.5 ft); `t/R` = outer sound wood shell thickness divided by trunk radius (Mattheck 0.30 threshold); `CRZ` = Critical Root Zone; `SRZ` = Structural Root Zone windthrow plate; `STIM` = Soil and Tree Integrated Monitoring.

## Slot 4: Answer-First Verdict, Phased Triage & Physical Falsifier
- **Headline Verdict:** Preserve Pecan (GTN-CI-204): the outer living wood cylinder exceeds the 0.30 Claus Mattheck stability threshold and qualifies for phased rhizosphere stewardship rather than removal.
- **Structural Truth:** The living wood cylinder retains a 15.8 cm outer shell across a 34.3 cm trunk radius (t/R = 0.46, above the 0.30 Claus Mattheck hollow-shell buckling threshold), anchored by a 10.19 ft (3.11 m) Structural Root Zone windthrow root plate.
- **Statutory & Seasonal Truth:** Under Georgetown Unified Development Code (UDC) Chapter 8 (Tree Preservation, Landscaping, and Fencing) (Georgetown, TX (tx-georgetown)), this 27 in DBH specimen is classified as Heritage with a statutory CRZ = 27 ft (8.23 m). Permit required: GTN-CI-204 Pecan (pruning). No active seasonal Oak Wilt pruning vector restriction is flagged for this specimen and jurisdiction.
- **Stewardship vs. Liquidation:** Preserving this living canopy asset retains $124,448 in 200-year holobiont equity ($13,432 classical CTLA depreciated timber appraisal and $8,100 municipal cash-in-lieu mitigation exposure if destroyed). Day-1 Stage 1 preservation triage starts at $2,114 compared against a one-time removal bid of $2,936, while the 5-year stewardship program delivers a 5.68x net practitioner margin multiplier over liquidation.
- **Physical Falsifier (STIM Kill Criterion):** If Year-1 terminal shoot extension drops below 10 cm or codominant union exhibits active seam separation, install non-invasive dynamic crown support per ANSI A300 Part 3.

### 3-Stage Phased Stewardship Triage (Total 5-Year Gross: $9,713 | Practitioner Net: $5,342)
- **Stage 1 (Day 1 (Immediate Triage)): Root-Collar Excavation, SGR Relief & Structural Audit** | Client investment: **$2,114** | Practitioner net: **$1,226**
- **Stage 2 (Months 6 to 18): 150 psi Radial AirSpade Decompaction & Biochar-Fungal Inoculation** | Client investment: **$4,179** | Practitioner net: **$2,140**
- **Stage 3 (Years 2 to 5): Native Companion Guild & Year-1 / Year-5 STIM Verification** | Client investment: **$3,420** | Practitioner net: **$1,976**

## Slot 5: Three-Tier Evidence Boundary & Oracle Provenance Anchors
### Tier 1: Deterministic Engine & Measured Biometrics
- Measured DBH (in): [[oracle:rca.structural.dbh_in=27]]
- Mattheck Sound Shell Ratio (t/R): [[oracle:rca.biomechanics.t_over_r=0.46]]
- Critical Root Zone Radius (ft): [[oracle:root_zone.crz_ft=27]]
- Structural Root Zone Radius (ft): [[oracle:root_zone.srz_ft=10.19]]
- 200-Year Holobiont Living Equity (USD): [[oracle:rca.valuation.holobiont_200yr_usd=124448]]
- CTLA 10th Ed. Depreciated Value (USD): [[oracle:rca.valuation.ctla_depreciated_usd=13432]]
- Municipal Cash-in-Lieu Exposure (USD): [[oracle:ordinance.cash_in_lieu_usd=8100]]
- Day-1 Stage 1 Triage Price (USD): [[oracle:rca.triage.stage1_usd=2114]]

### Tier 2: Literature & Statutory Calibration
- Claus Mattheck hollow-cylinder buckling criterion (t/R >= 0.30); Australian AS 4970-2009 SRZ; ANSI A300 Part 5 root-zone management; Nowak (1994, 2006) allometrics; Georgetown Unified Development Code (UDC) Chapter 8 (Tree Preservation, Landscaping, and Fencing).

### Tier 3: Explicit Unverified Epistemic Boundaries
- Zero unverified statutory or instrument gaps recorded in this brief.

## Slot 6: Cryptographic SHA-256 Receipt
- **Canonical Assessment SHA-256:** `5e52af5dfc4ff7755ae424d0a43201cc17c0de6a4dabd34b17eda2a57763010a`