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Biological Asset Risk Score

The financial cost of vine disease, in dollar terms.

BARS Institute translates GLRaV-3 and trunk disease into quantified NPV impairment, replant timing, and block-level capital priorities — structured for lenders, valuers, and transaction advisers.

Published Methodology · New Zealand
Framework Design
Lead Architect
Sarah Macfarlane
Expertise Basis
Former IANZ-Accredited Key Technical Person — Plant Virus Detection
Testing Standard
Processed via IANZ Accredited Laboratories (ISO/IEC 17025)
Methodology
MET-BARS-001 v1.2
Why it matters

Vine disease has a dollar figure. Most assessments don't show it.

Standard virus testing tells you a block is positive. It doesn't tell you what that means for recoverable value, lending security, or replant CAPEX. BARS Institute closes that gap — structured impairment evidence built specifically for the financial workflows that need it.

Financial outputs

What a BARS assessment delivers

Three outputs that RT-qPCR testing alone cannot produce. Each is derived from accredited diagnostics, epidemiological modelling, and discounted cashflow analysis.

NPV
Impairment in dollars

Present-day financial impact of GLRaV-3 and trunk disease, expressed per hectare and as a percentage of clean vineyard value. Derived from a 10,000-run Monte Carlo simulation and reported as median and downside-risk outcomes.

Reported as: Median and P95 downside, virus and GTD separately.
RDI
Replant Decision Intelligence

Projects when each block will reach its economic replant threshold, based on current disease burden, trunk disease progression rate, and productive life remaining.

Reported as: Replant trigger year and CAPEX planning horizon.
CAP
Capital Allocation Priorities

Ranks vineyard blocks by their contribution to total biological and financial risk, directing surveillance, remediation, and capital expenditure to the positions with the greatest economic consequence.

Reported as: Block risk ranking and tail-risk contribution table.

Underpinned by independently derived biological condition scores

BARS Virus Score (BVS)

RT-qPCR-confirmed GLRaV-3 prevalence expressed as a current-condition score from 0–100. Derived via Dorfman pooling inversion from ISO/IEC 17025 laboratory results.

BARS GTD Score (BGS)

Current trunk disease burden expressed as a score from 0–100, assessed across three tiers. Each figure carries a tier confidence label and disclosed uncertainty interval.

Built for decision-makers

BARS assessments are designed for agricultural lenders, registered valuers, accountants, and transaction advisers who need clear, defensible evidence on vineyard biological risk. The output is structured to support credit memoranda, impairment analysis, due diligence, and asset risk review.

Expertise basis

Sarah Macfarlane, Founder and Lead Biological Risk Analyst, brings rare expertise spanning accredited plant virus diagnostics, vineyard health surveillance, and biological asset risk assessment. As a former IANZ-accredited Key Technical Person within an ISO/IEC 17025 laboratory, she has developed diagnostic quality systems, trained laboratory personnel, overseen plant virus testing programmes, and managed commercial grapevine health surveillance and reporting. Her experience spans the full spectrum of biological risk — from diagnostic detection through to vineyard-level asset management decisions.

Methodology and standards

BARS assessments follow a published methodology statement (MET-BARS-001), with all key assumptions, calibration bases, and sensitivity ranges disclosed. Diagnostic samples are submitted to independent IANZ-accredited laboratories for RT-qPCR analysis, supported by chain-of-custody documentation from collection through to laboratory receipt.

Framework Summary
Framework Lead
Sarah Macfarlane
Technical Foundation
Designed to BARS Institute standard specifications
Diagnostic Testing
Executed exclusively by independent, IANZ-accredited labs
Methodology Document
MET-BARS-001 v1.2
Monte Carlo Runs
10,000 per block
Independence
No vineyard management, supply, or purchase conflicts
Framework alignment

This framework supports vineyard impairment and fair value decision-making in line with NZ IAS 36, NZ IAS 41, NZ IFRS 13, and NZ IAS 16 considerations. It is designed to provide auditable biological risk evidence for professionals carrying financial or governance responsibility.

NZ IAS 36
NZ IAS 41
NZ IFRS 13
NZ IAS 16

Enquire about an assessment

Tell us about the property, blocks, and context. We'll confirm scope and fee within one business day.

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BARS outputs are decision-support evidence for engaging professionals. They do not replace a registered valuation, accounting opinion, or credit decision.