Case 1: Austin Heritage Live Oak (30 in DBH)

STATUS: OA-RCA-v2:ATX-QV-101 | drafts complete: 1/1 | unverified citations: 0

# LEO-RCA Profile 01 Evidentiary Stewardship Brief (ATX-QV-101)

## Slot 1: Epistemic Status & Workstream Header
- **Workstream ID:** `OA-RCA-v2:ATX-QV-101`
- **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:** *Quercus virginiana* (Live Oak), tag `ATX-QV-101`
- **Geospatial Anchor:** Plus Code `86247784+VP` (Lat `30.27`, Lng `-97.74`)
- **Governing Municipal Code:** City of Austin Land Development Code (LDC) Title 25, Chapter 25-8, Subchapter B (Tree and Natural Area Protection); Environmental Criteria Manual (ECM) Section 3 (Austin, TX (tx-austin))
- **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 Live Oak (ATX-QV-101): 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 14.5 cm outer shell across a 38.1 cm trunk radius (t/R = 0.38, above the 0.30 Claus Mattheck hollow-shell buckling threshold), anchored by a 10.77 ft (3.28 m) Structural Root Zone windthrow root plate.
- **Statutory & Seasonal Truth:** Under City of Austin Land Development Code (LDC) Title 25, Chapter 25-8, Subchapter B (Tree and Natural Area Protection); Environmental Criteria Manual (ECM) Section 3 (Austin, TX (tx-austin)), this 30 in DBH specimen is classified as Heritage with a statutory CRZ = 30 ft (9.14 m). Permit required: ATX-QV-101 Live Oak (pruning). Seasonal Ceratocystis fagacearum (Oak Wilt) vector precautions apply: avoid non-emergency oak pruning February through June and seal all fresh wounds within 10 minutes.
- **Stewardship vs. Liquidation:** Preserving this living canopy asset retains $218,609 in 200-year holobiont equity ($13,699 classical CTLA depreciated timber appraisal and $18,000 municipal cash-in-lieu mitigation exposure if destroyed). Day-1 Stage 1 preservation triage starts at $2,261 compared against a one-time removal bid of $3,140, while the 5-year stewardship program delivers a 6.35x net practitioner margin multiplier over liquidation.
- **Physical Falsifier (STIM Kill Criterion):** If Year-1 terminal shoot extension remains below 6 cm or upper crown dieback exceeds 12%, re-inspect for subsurface utility trench root severance or oak wilt vascular streaking.

### 3-Stage Phased Stewardship Triage (Total 5-Year Gross: $11,604 | Practitioner Net: $6,382)
- **Stage 1 (Day 1 (Immediate Triage)): Root-Collar Excavation, SGR Relief & Structural Audit** | Client investment: **$2,261** | Practitioner net: **$1,311**
- **Stage 2 (Months 6 to 18): 150 psi Radial AirSpade Decompaction & Biochar-Fungal Inoculation** | Client investment: **$5,139** | Practitioner net: **$2,637**
- **Stage 3 (Years 2 to 5): Native Companion Guild & Year-1 / Year-5 STIM Verification** | Client investment: **$4,204** | Practitioner net: **$2,434**

## Slot 5: Three-Tier Evidence Boundary & Oracle Provenance Anchors
### Tier 1: Deterministic Engine & Measured Biometrics
- Measured DBH (in): [[oracle:rca.structural.dbh_in=30]]
- Mattheck Sound Shell Ratio (t/R): [[oracle:rca.biomechanics.t_over_r=0.38]]
- Critical Root Zone Radius (ft): [[oracle:root_zone.crz_ft=30]]
- Structural Root Zone Radius (ft): [[oracle:root_zone.srz_ft=10.77]]
- 200-Year Holobiont Living Equity (USD): [[oracle:rca.valuation.holobiont_200yr_usd=218609]]
- CTLA 10th Ed. Depreciated Value (USD): [[oracle:rca.valuation.ctla_depreciated_usd=13699]]
- Municipal Cash-in-Lieu Exposure (USD): [[oracle:ordinance.cash_in_lieu_usd=18000]]
- Day-1 Stage 1 Triage Price (USD): [[oracle:rca.triage.stage1_usd=2261]]

### 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; City of Austin Land Development Code (LDC) Title 25, Chapter 25-8, Subchapter B (Tree and Natural Area Protection); Environmental Criteria Manual (ECM) Section 3.

### 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:** `035bccca002d2569205cfad3a434f4f4bbd94ea20e4eeb470b279b60ab3dac7d`