Restoring links between records and crowns

What changed

This release restores 4,661 record-to-crown links across 4,362 crowns: 3,518 Auckland Transport and 470 Parks records from the Council tree register, and 673 records of LiDAR-detected trees from earlier releases.¹ Original record IDs, source coordinates and survey histories remain intact. Former generated representatives are retained as linked records.

How links were restored

Release 5 required a record’s source position to fall inside the filled crown polygon. Small positional offsets and holes could therefore leave a longstanding tree record without a crown while a new detection represented its crown. Release 5.1 also considers strong continuity between the record’s earlier and current crown, a small edge distance, compatible height, and the absence of competing crowns or conflicting recorded taxa.²

What a link means

A restored link is spatial evidence. It does not prove that all records within a shared canopy describe one organism. Ambiguous cases remain for review: 28,735 audited candidates were not automatically attached. “No crown linked” does not mean a tree is missing or dead.

Consistent records and estimates

The map, tree panels, property summaries, totals and KYTE nearby suggestions use the repaired snapshot. Each current crown contributes one set of benefit estimates. Those scenarios use the same release 5 equations and keep their existing uncertainty. The two KYTE ground visits accepted before this release remain available.

Crown geometry

The polygon geometry is unchanged, including known holes and clipped edges. The next geometry candidate will use native-resolution LINZ imagery, the LiDAR returns and researcher-drawn reference crowns. It must distinguish erroneous gaps from real gaps, and crown shape from source-record identity. Existing growth-form research for release 6 does not itself redraw crowns.