- Sample
- 2,000+ mapped or screened · 48 deep-scored
- Source
- Nearmap aerial capture
- Cadence
- 2 surveys / year
- Review
- Every published result human-reviewed
Evidence stack
Four forensic layers. One verifiable sightline. Measured, not guessed.
Layer 01
Aerial capture
Each market is captured on high-resolution Nearmap survey cycles. Multi-spectral extraction over a single survey yields aligned surface, terrain and vegetation products, so canopy extent and height measurements always come from the same moment in the same capture.
Layer 02
Deterministic geometry
Panel faces, sight cones and tree crowns are modelled as vector geometry. Subtracting terrain height from surface height gives the true height of every crown near a sightline. The compute is deterministic: the same inputs always produce the same score. Judgement enters exactly once, at review, before a result is published.
Layer 03
Ray-cast occlusion
A ray-cast from the driver's position targets each panel's line of sight and measures how much of the face survives the vegetation between them. The output is an obstruction score per panel face, from the worst viewpoint on the approach.
Layer 04
Species and growth forecast
Species come from council tree records where available, joined to each detected crown, with imagery-based classification extending coverage where records stop. Species sets the growth curve: a plane tree and a eucalypt close a sightline at very different speeds. Growth applied across a zero-to-60-month window gives each panel its occlusion horizon, the month a tree is expected to cross the sign face.
Survey cadence
Surveyed twice a year, forecasted in between.
Panels are surveyed twice per year on aerial capture cycles. Between passes, the species growth model forecasts regrowth, so every score in the Index is either a fresh measurement or a dated forecast, never a stale reading.
Accuracy & review
Raw detection is wrong about one panel in ten. So a person reviews every result we publish.
Validated against manual review, Kestryl's raw detection disagrees with a human scorer on roughly one panel in ten, which is why no result is published without review. We publish the raw figure because the industry has no baseline at all: every score carries its survey date and traces back to the imagery it was measured from.
From score to action
Which trees can actually be pruned.
In our Australian coverage, every tree also carries its local planning-overlay status. Heritage-protected trees are flagged as plan-around; trees under vegetation or landscape controls are flagged as permit-required; unprotected trees can be pruned without a permit. That turns a visibility problem into a ranked, permit-aware worklist. Overlay coverage is currently Victoria only, expanding with the Index.
Terms used on this page are defined in the glossary. Full technical documentation ships with each quarterly report.