Survival rate at horizon (percent)
Definition
Tree individuals observed alive at a declared horizon divided by the tree individuals planted at that site on the day of planting that were observed at that horizon, as a percentage: unobserved trees leave both numerator and denominator and their count is reported alongside. The frame is the planting-day trees, never adjusted for replacements. Rolled up across sites by summing numerators and denominators, never by averaging site rates. Calculated over the planted-with-monitoring stratum from T1 onwards; unscheduled observations never count (ADR-0020).
purpose
To report the share of planted trees alive at each horizon, comparable across sites, species, strata and programmes.
rationale
Survival is the outcome the funder contracts on and the programme is judged by; fixing the frame to the planting-day trees, excluding the unobserved from both sides and reporting their count keeps the figure honest and stops a small site skewing the programme figure.
Classification
- Result level: Outcome
- Outcome domains: Climate resilience, Green-space access and amenity, Learning and scalability
- Unit of observation: Tree individual
- Activity types: Monitoring visit
- Approval status: Approved
- Unit of measure:
PERCENT
Collections
- 2026 core indicator set: The fifteen indicators a 2026 project under the standard reports: the site preconditions and assessments, delivery and planting, education and care, and the survival family to T2. Every member is approved and served by an approved methodology whose records exist in the standard; the monthly and final reports are queries over approved claims at these indicators. Module indicators sit outside it.
- Survival family: The outcome indicators computed from one monitoring visit’s tree observations under NCGS-M001: trees alive at horizon, survival rate, trees by condition class, establishment rate; and for trees delivered with monitoring, planting uptake at T0+ and survival against the trees acknowledged at handover (ADR-0031).
Methodologies that serve it
- NCGS-M001 — Census count of tree state at a declared horizon
- NCGS-M002 — Stratified-sample estimate of tree state at a declared horizon
Where it can be claimed, by stratum and horizon: the claims table.