A housing number is a spatial address. In a propagation nursery managing dozens of clone accessions across numbered rooting beds, it's the field that makes a measurement mean something beyond a timestamp and a meter reading.
How Nursery Monitoring Fails Without Spatial Granularity
The standard error in tree nursery fertigation management is treating the bulltank as the primary quality control point. You mix to the target EC, you verify the pH, and you assume the system delivers that solution uniformly. That assumption breaks down at scale. Pressure variations across long drip lateral runs, partial emitter blockages that reduce flow at specific housing beds, substrate salt buildup in rooting media that's been cycling longer than neighboring beds — these are all localized deviations that a bulltank reading will never detect.
This template is structured around the principle that each measurement event belongs to a physical location. The Lokasi field is populated by barcode scan — the barcode on the housing bed, the nursery zone marker, or the drip lateral label — which eliminates manual location entry errors and ties every reading to a fixed physical reference. The No.Housing integer field then pinpoints the exact rooting housing number within that location, giving you sub-zone resolution that a location field alone doesn't provide.
Together, these two fields let you ask: is housing 14 in Zone B consistently reading higher EC Drip than housing 7 in the same zone? That's a maintenance question about emitter flow uniformity, not a fertigation formulation problem. You'd never separate those two root causes without per-housing data.
What the Four EC-pH Measurement Points Tell You
Bulltank EC and pH are the formulation control points. Drip EC and pH confirm what's actually being delivered. EC Pasir+Air and pH Pasir+Air measure the rooting substrate condition — the cumulative effect of everything that's been applied to the media over the housing's service life. EC Soil Sucker and pH Soil Sucker are rhizon-extracted pore water readings from directly within the root zone.
Each of these four data points can diverge, and the divergence pattern tells you what's wrong. Bulltank EC 2.1, Drip EC 1.4 across multiple housings in a zone: the injector is under-dosing that lateral. Drip EC 2.1, Soil Sucker EC 3.8 in a housing that's been running for eight weeks: substrate salt accumulation needs a flush. Pasir+Air pH 7.2 when Drip pH is 5.8: the rooting media has high alkalinity buffering capacity that's neutralizing your adjusted solution before it reaches the root.
EC Air Bersih and pH Air Bersih establish the baseline. Source water quality in tropical locations with seasonal variation can shift significantly — if your source EC climbs from 0.12 to 0.28 mS/cm between dry and wet season, your prepared solution concentration is changing even if you're using the same fertilizer recipe.
The Clone List Across Housing
The Clone field covers the full IND series accessions alongside CEP, CGP, and Pinus regional provenance material (Tapsel, Aceh, Kerinci). Different clones are typically distributed across different housing blocks in a production nursery. When you stratify the EC and pH dataset by Clone and housing number, you can see whether nutritional responses differ by genotype, or whether apparent clone differences are actually position effects — housing beds on the outer rows of the greenhouse receiving more direct light and higher evapotranspiration demand, resulting in substrate drydown that concentrates EC faster than interior beds.
That distinction, between genetic sensitivity and microenvironmental position, only becomes visible when both Clone and No.Housing are recorded per measurement event.