When the Logger Disappears and You Have No Installation Record
The sensor is gone. Sometime between your September site visit and the December data pull, a TMS-4 soil logger at the 2m depth position on Tree 3 went missing — taken by a field technician who thought it was spare equipment, knocked loose by a falling branch, or simply failed and was removed by someone who did not log the action. You have the data through September. You have a gap you cannot explain to the funding agency. And you have no written record of where exactly that logger was installed — distance from stem, depth, orientation — because the installation was done fast, in the rain, and nobody entered it into the system.
That is the situation this template was built to prevent.
The Geometry Fields That Rebuild Your Sensor Network From Scratch
RootPoint_distance_from_stem_m and root_diameter_stem_cm are the two fields that let you reinstall a root-monitoring sensor in exactly the same position as the previous one. Root diameter at the measurement point tells you which lateral root was instrumented. Distance from stem tells you where along that root's horizontal extent the sensor bracket was placed. Without both, you are guessing at reinstallation and introducing measurement discontinuity that invalidates inter-period comparison.
Stem_height_m performs the same function for point dendrometers. TMS dendrometers installed at 1.3m produce different thermal buffering characteristics than those installed at 0.8m on a suppressed individual, and both differ from an installation at 2.1m above a buttress. The height is not ambient data — it is a configuration parameter. When the sensor is replaced, height must match or the xylometric readings are not comparable across installation periods.
tree_dbh_cm at installation time is your baseline. The whole point of continuous dendrometry is to measure radial increment relative to a starting state. If you do not have the DBH at the moment of installation recorded alongside the instrument configuration, every increment reading is a delta with an unknown origin.
What the Database Looks Like When the Network Scales
A single-species deployment on five trees generates at most twenty records — stem, root, meteo, and soil sensors per individual. Manageable without a database. Add a second species, expand to a second elevation gradient, and add midseason sensor swaps, and you are at forty to sixty records with overlapping Instrument_ID assignments that no spreadsheet can disambiguate reliably.
The Instrument_ID field paired with Instrument_Type — TMS point dendrometer, TMS-4 soil, TMS-4 soil 2m, or HOBO U23 — creates a unique instrument-level identity that survives reassignment. The same physical logger moved from Tree 2 stem to Tree 4 root mid-season is a new installation record, not an edit of the previous one. Immutable installation records with timestamps are what make retrospective data cleaning possible when the raw telemetry shows anomalies that could be sensor drift, installation damage, or legitimate biological signal.
The Lat-Lon and Elevation_m fields close the spatial register. Elevation in meters above sea level is the first covariate any ecophysiology reviewer will request for a multi-site dendrometry study, and having it per-installation rather than per-plot gives you the resolution to model microtopographic effects on stem water deficit response.