Secondary Features — Tree Inspections (BS3998)

Overview

Tree Inspection secondary features automate BS3998 arboricultural surveys. From a parent tree point feature, Soarvo auto-generates a Root Protection Radius (RPR) circle and a crown spread polygon. From a parent hedge linear feature, it generates a hedge centreline and a hedge-extent polygon. RPR is calculated automatically from stem diameters.

ℹ️ App version: Soarvo Mobile 0.0.130+.

Tree Inspection — Parent Feature Type Setup

Create a point feature type with these attributes:

_secondary_feature — default !MODIFIER-HIDE;TreeInspection
_root_feature_type_name — default !MODIFIER-HIDE;{YourRootTypeName} (e.g. TreeRoot)
_crown_feature_type_name — default !MODIFIER-HIDE;{YourCrownTypeName} (e.g. TreeCrown)
StemCnt (numeric, integers) — number of stems
StemDia1 through StemDia6 (numeric, decimals allowed, millimetres) — each with modifier !MODIFIER-SHOWWHEN $StemCnt != null && $StemCnt>N where N matches the stem index
RootRadius (numeric) — default value !CALCRPR (auto-calculates RPR in metres, capped at 15m)
CrownSprd (radio) — options even, uneven
For uneven spread: NorthSprd, EastSprd, SouthSprd, WestSprd — each with !MODIFIER-SHOWWHEN $CrownSprd=='uneven'
For even spread: EvenSprd — with !MODIFIER-SHOWWHEN $CrownSprd=='even'

💡 Tip: !CALCRPR uses StemDia1 × 12 for single-stem trees; for 2–5 stems uses √(sum of squared diameters) × 12; for 6+ stems averages from StemDia1 and StemCnt. Cap is 15 metres.

Tree Inspection — Child Root Feature Type

Create a linear feature type with the exact name set in _root_feature_type_name. Soarvo generates a circular line of radius RootRadius around the tree point.

Tree Inspection — Child Crown Feature Type

Create an area (polygon) feature type with the exact name set in _crown_feature_type_name. Soarvo generates either a circular polygon (for even spread) or an elliptical polygon (for uneven spread with the four directional measurements).

💡 Tip: Add any attributes to root/crown feature types that you want auto-copied from the parent (e.g. species, condition).

Hedge Inspection — Parent Feature Type Setup

Create a linear feature type with these attributes:

_secondary_feature — default !MODIFIER-HIDE;TreeInspection
_hedge_edge_feature_type_name — default !MODIFIER-HIDE;{YourHedgeEdgeType}
_hedge_centre_feature_type_name — default !MODIFIER-HIDE;{YourHedgeCentreType}
width (numeric, metres) — hedge width
Surveyed (radio) — options left, right, centre

Surveyed behaviour:

left — surveyed line is the left edge; centreline offsets to the right by half the width
right — surveyed line is the right edge; centreline offsets left by half the width
centre — surveyed line is already the centreline; no offset

Hedge Child Feature Types

Hedge Centre (linear) — name matches _hedge_centre_feature_type_name. The centreline of the hedge.
Hedge Edge (polygon) — name matches _hedge_edge_feature_type_name. A buffer polygon representing the full hedge extent.

Field Workflow

Tree: create a parent tree feature → set position → enter StemCnt, StemDia values, CrownSprd type, spread measurements → save. Root and crown auto-generate.

Hedge: create a parent hedge feature → draw the line along the surveyed edge or centre → enter width and Surveyed side → save. Hedge edge polygon and centreline auto-generate.