Tree Surveys + GIS NSW — Survey-Grade Tree Mapping Your Design Team Can Actually Use

Two main differences. First, position accuracy: regular consulting-arborist surveys typically capture tree positions by pacing from known boundaries, or using phone GPS (5–15m error). Our Trimble R2 + RTX setup delivers centimetre-level accuracy under open sky and sub-metre under canopy — survey-grade, the same accuracy class your detail surveyor delivers. Second, deliverable format: regular tree surveys are delivered as PDFs. Ours include the underlying spatial data as actual GIS-ready layers in your design team’s preferred format (AutoCAD DWG, GeoPackage, ESRI Shapefile, KMZ, etc.) — so the trees can be design entities, not sketched approximations.

Standalone GNSS receivers (including phone GPS) get position accuracy of about 3–15m because the raw satellite signals are affected by atmospheric distortion, satellite clock errors and other systematic errors. Correction services like Trimble RTX provide real-time correction data via satellite that compensates for these errors, bringing accuracy down to a few centimetres under open sky and sub-metre under canopy or partial obstruction. Without correction, GNSS isn’t survey-grade. With Trimble RTX, our Trimble R2 receiver is.

Yes — that’s the point. Tell us what your design team uses (AutoCAD, Revit, ArchiCAD, QGIS, ESRI ArcGIS, or a project-specific CDE), what coordinate system the project is in (typically MGA Zone 56 for NSW projects), and what naming conventions / attribute schemas you need the tree data to follow. We’ll deliver in your format with the schemas matched. Multiple formats from one engagement are standard, no per-format surcharge.

Open sky: typically 2–5cm horizontal with Trimble RTX. Light canopy: 10–30cm. Heavy canopy (dense forest, narrow urban lots with multi-storey trees overhead): typically sub-metre, sometimes 1–2m where satellite reception is genuinely degraded. We document the accuracy class achieved at each location in the survey report so your design team knows what tolerance the data supports. For constrained sites where survey-grade accuracy is critical, we can also tie into local control points or co-located detail-survey reference marks if your project has them.

Highly variable. A 20–30 tree small commercial site is typically half a day on site. A multi-hundred-tree subdivision can be 3–5 days across multiple visits. Access constraints, vegetation density, and the per-tree attribute capture requirements all affect the rate. We’ll estimate the field component at scoping based on your site address, tree count and access conditions.

Yes — we can process existing tree data (from a surveyor’s detail survey, an old asset register, even paper records) into a clean GIS deliverable, including AS 4970-2025 NRZ/TPZ/SRZ polygon generation against the existing positions. This is the engagement type our old “GIS Analyst” service page covered. Output formats and processing options are the same as a full survey-and-GIS engagement; the difference is we’re not collecting the positions ourselves.

“Survey-grade” in this context means the position accuracy class meets the standards detail surveyors typically work to (centimetre-level for open-sky GNSS). It does NOT mean we’re a registered cadastral surveyor — tree positions captured by our Trimble R2 aren’t a substitute for a registered survey of property boundaries, easements or cadastral marks. For projects requiring a registered survey, we work alongside your appointed surveyor and deliver the tree-attribute layer that integrates with their cadastral baseline.

AS 4970-2025 (Protection of Trees on Development Sites — the source for NRZ/TPZ/SRZ polygon generation), IACA STAR (retention value assessment methodology), Arboriculture Australia Minimum Industry Standards, and project-specific coordinate systems and attribute schemas as the engagement requires. Our QGIS workflow is built around these standards so the output is consistent across projects.