NCGS Observation Horizons
T0 to T5, with T0+ between T0 and T1: when after the anchor event an observation is made, each with a minimum and maximum offset in days. An observation declares its horizon; one whose date falls outside the window, or on a visit that declares none, is an unscheduled observation (ADR-0020). Gaps between windows are deliberate.
T0 baseline
Before or at the anchor event: the site or tree as found before planting.
T0+ post-handover check
A planting check 1 to 14 days after the anchor, for a handed-over tree the handover date: whether the handed-over tree has been planted, and where; not a survival horizon (ADR-0031).
T1 four weeks
The end of the first four weeks after planting, 21 to 28 days. An observation inside the first three weeks is unscheduled (ADR-0020).
T2 early establishment
About three months after planting. A common contract horizon for early establishment.
T3 one year
About one year after planting; the horizon at which establishment is judged.
T4 two to three years
Two to three years after planting; canopy and shade become measurable.
T5 five years and beyond
Five years or more after planting; no upper bound.