> ## Documentation Index
> Fetch the complete documentation index at: https://badixth-dc85e378.mintlify.site/llms.txt
> Use this file to discover all available pages before exploring further.
# Healthy NDVI Ranges for Rubber Across Planting Environments
> Indicative healthy NDVI bands for Hevea rubber across mineral upland, hilly / sloping, coastal lowland, and peat environments, by stand age and wintering cycle.
Rubber (*Hevea brasiliensis*) is a perennial tree crop with a closed, tall canopy that dominates satellite reflectance for most of its productive life. Healthy NDVI is driven by **stand age**, **planting environment**, and the annual **wintering** (leaf fall and refoliation) cycle, which causes a predictable NDVI dip every year that is easily mistaken for stress.
This page lists indicative healthy NDVI bands for **Malaysian rubber plantations** by environment and stand age so you can interpret the Health tab correctly for the block in front of you. Bands are aligned to Malaysian Rubber Board (MRB / LGM) planting recommendations and RRIM clone series.
For the generic Health tab workflow, see [Crop Health](/guides/crop-health-monitoring).
## Rubber planting environments at a glance
| Environment | Soil / terrain | Interpretation risk |
| --------------- | ------------------------------------------------ | ------------------------------------------------------------------------------------------------------- |
| Mineral upland | Well-drained inland mineral soils, gentle slopes | Baseline. Cleanest NDVI signal. Bulk of Malaysian rubber sits here. |
| Hilly / sloping | Undulating to steep terrain, terraced | Mild slope-shadow effects; smaller than in temperate zones because Malaysia is near the equator. |
| Coastal lowland | Flat, high water table, alluvial clay | Waterlogging dips after heavy rain. Common in Kedah, coastal Perak (Bagan Datuk), and coastal Selangor. |
There is no single peak NDVI for an environment. A band resolves against environment **and** stand age together, in the per-environment tables below. See [How a band resolves](/snippets/band-resolution).
Ranges on this page are indicative bands drawn from published Sentinel-2 and Landsat rubber studies and MRB / RRIM / IRRDB agronomy references. The platform refines them automatically once it has one or more years of block history.
Rubber on **peat** is rare in Malaysia; Malaysian peat is overwhelmingly under oil palm. If you have rubber on peat, treat the mineral-upland bands as a starting point and let the platform refine from block history, expecting peak NDVI \~0.05 lower.
## Stand age drives the NDVI curve
Malaysian rubber runs a **25 – 30 year economic cycle**: **5 – 7 years of immaturity** before opening for tapping, then **20 – 25 years of tapping**, then replanting. RRIM 2000 / 3000 series latex-timber clones typically reach tappable girth (50 cm at 150 cm from union) at **year 5 – 6** on good mineral upland; slower sites push this to year 6 – 7. The table below names the stand-age classes and what the canopy is doing in each. **It carries no NDVI numbers**: a band resolves from stand age *and* planting environment together, so the numbers live in the per-environment tables below. See [How a band resolves](/snippets/band-resolution).
| Stand age | Canopy state | Notes |
| ------------------------------------ | ---------------------------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| 0 – 1 year (newly planted) | Bare inter-row, small seedlings | Legume cover crops (Mucuna, Pueraria, Calopogonium) dominate the signal. |
| 1 – 3 years (immature) | Saplings expanding, ground still visible | Uniform rise expected; patches flag replanting failures. |
| 3 – 5 years (pre-tapping) | Canopy closing | Steady climb toward closure. Girth check for tapping readiness at year 5. A stand here has **not** closed canopy, and reads lower than a tapped stand for that reason alone. |
| 5 – 7 years (opening) | Closed canopy, tapping begins | Canopy closure and first tapping around year 5 – 7. |
| 7 – 20 years (prime tapped) | Closed, mature canopy | Peak NDVI plateau. Small dips may reflect tapping intensity or disease. |
| 20 – 25 years (late tapped) | Closed, taller trees | Slight decline is normal; sharp drops flag disease or over-tapping. |
| > 25 years (senescent / pre-replant) | Thinning canopy | Plan replanting; NDVI alone cannot tell age-decline from disease. No per-environment band is published for this class — the platform resolves it from block history or says so. |
NDVI saturates on closed rubber canopies. From year 5 – 6 onward (once canopy closes), switch to **NDRE** or **EVI** for finer differentiation between healthy and mildly stressed blocks.
## The wintering dip is normal
Every year, mature rubber trees drop their leaves (**wintering**) then refoliate over 4 – 8 weeks. This causes a repeatable seasonal NDVI dip of **0.10 – 0.25** that lasts roughly 6 – 10 weeks. In Peninsular Malaysia the wintering window is typically **February to March**, extending into early April in some clones and northern states (Perlis, Kedah, north Perak). Sabah and Sarawak run slightly later and less synchronized due to the equatorial rainfall pattern.
| Wintering stage | Duration | NDVI change | Notes |
| ------------------ | ----------- | -------------------------- | ------------------------------------------------------ |
| Pre-wintering | – | At plateau | Normal peak NDVI. |
| Leaf fall | 2 – 4 weeks | Drop of 0.10 – 0.25 | Sharpest decline. Do not flag as stress. |
| Bare / refoliation | 2 – 4 weeks | Trough at 0.55 – 0.70 | Depends on clone and completeness of defoliation. |
| Recovery | 2 – 4 weeks | Rapid rise back to plateau | NDVI returns to pre-wintering levels within \~8 weeks. |
A once-a-year NDVI drop of 0.10 – 0.25 in Feb – Apr on mature Malaysian rubber is almost always wintering, not disease. Confirm by comparing to the same block in previous years. A drop **outside** the historical wintering window, or one that fails to recover within 8 – 10 weeks, is the real stress signal.
Once one full year of history exists on a rubber block, switch to **Anomaly** view. It compares each pixel to the same block on the same calendar week last year. Rubber sits on a plateau for most of the year, so outside the wintering window the calendar is a good proxy for stage and the comparison is sound.
### Anomaly is refused inside the wintering window
Wintering does not fall in the same weeks every year. It shifts by clone, it runs later in the northern states, and Sabah and Sarawak are later still and less synchronized. So the same calendar week can be bare leaf-fall one year and full canopy the next.
A calendar-aligned anomaly across that boundary measures **the shift in wintering timing, not the health of the block** — and it can report a −0.20 anomaly on a block that is doing exactly what it should.
Inside a block's wintering window the platform states **no anomaly figure**, and says why. This is deliberate. A figure that may be entirely an artefact of timing is worse than no figure, and a caution attached to it does not fix that.
Judge the block against the **wintering stage table above** and the recovery test below. **Not against its stand-age band** — see the next section for why.
The refusal is not a gap in the data. **The question the anomaly answers cannot be asked until the two years are aligned on the same event**, and calendar week does not align them. A future revision may anchor year-over-year comparison on each block's own observed leaf-fall onset rather than on the calendar, which would let the comparison run through the window; until then, the refusal is the honest answer.
### Inside the window, the stand-age band does not apply either
A mature rubber block **is supposed to be out of its band during wintering.** The prime tapped band is 0.78 – 0.90. The wintering trough is 0.55 – 0.70. Those do not overlap, so for six to ten weeks a year a perfectly healthy tapped block reads **below band by design**.
**No below-band finding fires on a rubber block inside its wintering window.** The wintering stage table *is* the band for that window; the stand-age band is suspended, not merely supplemented.
A block reading 0.62 in March has not lost 0.2 of health. It has dropped its leaves, which is what the species does.
**The suspension is one-sided, and deliberately so.** Below-band is suppressed because it is expected. **Above-band still fires**, because a mature block sitting at plateau in the middle of its wintering window has *not* wintered on schedule — and that is a real finding, not an absence of one. See [A reading above the band](#a-reading-above-the-band).
Two consequences worth stating, because both have been got wrong before:
* **The suspension is per block, not per calendar.** It follows the block's own observed leaf fall. A Sarawak block and a Kedah block are not suspended in the same weeks.
* **A dip that fails to recover is not covered by the suspension.** Recovery is the test that stays live throughout — see the warning above. The suspension excuses the trough, never the failure to climb out of it.
## A reading above the band
The band describes what healthy looks like at this stand age in this environment. It is not a floor. **A reading above the band is a finding, not the absence of one** — see [How a band resolves](/snippets/band-resolution).
On rubber there are three cases, and they do not overlap.
**Immature and pre-tapping stands.** The canopy is not closed, so legume cover crops and inter-row vegetation contribute much of the signal. An above-band reading usually means the cover is doing well or the planting date on record is wrong — not that the trees are ahead.
**Inside the wintering window.** This is the one that matters most on rubber. A block reading at plateau in February or March **has not wintered on schedule**. That is a real finding: a clone that winters later, a northern-state or East Malaysia shift, or a planting and clone record that does not match the tree in the ground. Wintering is not optional on mature *Hevea*, so its absence is information.
**Tapped stands outside the window.** The canopy is closed and NDVI has saturated. An above-band reading here is not a finding.
**Saturation carve-out.** On closed rubber canopies NDVI stops discriminating. The platform raises no above-band finding on a saturated reading and says the reading has saturated before naming its band.
On rubber this covers everything from canopy closure onward — the whole tapping life of the stand. NDRE keeps discriminating past that point, but this documentation publishes **no NDRE band** to read against, so an above-band question on a tapped block currently goes to a scout rather than to the index.
## Mineral upland
Well-drained inland mineral soils on gentle slopes. This is the baseline used by the default rubber preset in [Crop Health](/guides/crop-health-monitoring) and covers the majority of Malaysian rubber planted in Perak, Negeri Sembilan, Johor, Pahang, Kedah, and inland Sarawak. Uniform soil, stable moisture, and even canopy give the cleanest NDVI signal.
| Stand age | Healthy NDVI | Notes |
| ------------- | ------------ | --------------------------------------------------------------- |
| 0 – 1 year | 0.25 – 0.45 | Cover crop establishment visible within 3 – 6 months. |
| 1 – 3 years | 0.40 – 0.65 | Uniform rise expected block-wide. |
| 3 – 5 years | 0.60 – 0.80 | Canopy closure typically at year 5 for RRIM 2000 / 3000 clones. |
| 5 – 7 years | 0.78 – 0.88 | Opening for tapping around year 5 – 6 on good sites. |
| 7 – 20 years | 0.80 – 0.90 | Peak plateau. |
| 20 – 25 years | 0.75 – 0.88 | Gentle decline. |
## Hilly / sloping
Undulating to steep terrain, often terraced. Common in Perak, Pahang, Negeri Sembilan, and highland belts. Because Malaysia sits at 1° – 7°N, sun angles are nearly overhead year-round, so slope-aspect bias is **weaker than in temperate zones** but still present in early morning and late afternoon imagery, and on steeper (> 20°) slopes.
| Stand age | Healthy NDVI | Notes |
| ------------- | ------------ | --------------------------------------------------------------------------------- |
| 0 – 1 year | 0.22 – 0.42 | Terrace edges show as bare soil strips. |
| 1 – 3 years | 0.38 – 0.62 | Slightly slower canopy build on erosion-prone slopes. |
| 3 – 5 years | 0.55 – 0.78 | Canopy closure delayed by \~6 – 12 months on steep sites. |
| 5 – 7 years | 0.72 – 0.85 | First tapping often at year 6 – 7 on hilly blocks. |
| 7 – 20 years | 0.78 – 0.90 | Shaded-slope pixels read 0.02 – 0.05 lower than exposed slopes at low sun angles. |
| 20 – 25 years | 0.72 – 0.85 | |
On sloping blocks, prefer **relative** comparisons (Anomaly view or same-block year-over-year) over absolute NDVI thresholds. Slope-shadow bias is systematic per pixel and cancels out when comparing the same pixel to itself.
## Coastal lowland
Flat coastal blocks on alluvial clay with a high water table. In Malaysia, this includes coastal Kedah, Bagan Datuk (Perak), and coastal Selangor. Less common than oil palm in this environment, but a real category for older rubber estates. Yields are strong when drainage is maintained; heavy rain events cause temporary waterlogging and short-lived NDVI dips.
| Stand age | Healthy NDVI | Notes |
| ------------- | ------------ | ------------------------------------------------------------- |
| 0 – 1 year | 0.20 – 0.40 | Watch for standing water in inter-rows after rain. |
| 1 – 3 years | 0.35 – 0.60 | Slightly slower canopy build than mineral upland. |
| 3 – 5 years | 0.55 – 0.78 | Root disease risk (white root, red root) higher in wet soils. |
| 5 – 7 years | 0.70 – 0.84 | |
| 7 – 20 years | 0.75 – 0.86 | Post-rain dips of 0.03 – 0.06 are normal. |
| 20 – 25 years | 0.72 – 0.84 | |
On coastal lowland blocks, cross-check NDVI dips against the **NDWI** layer and rainfall records before flagging stress. A synchronized NDWI rise with an NDVI dip usually means transient waterlogging, not decline.
## Choosing the right environment on a block
From the block overview, open **Settings** in the top-right.
Under **Crop**, choose **Rubber**. Additional rubber options appear.
Choose the clone based on the current MRB Planting Recommendations:
* **RRIM 2000 series** (RRIM 2001, 2002, 2007, 2008, 2014, 2015, 2020, 2023, 2024, 2025, 2026) — current latex-timber standard
* **RRIM 3001** — newer latex-timber release
* **RRIM 900 series** (RRIM 928, 929) — still planted, older latex clones
* **PB series** (PB 260, PB 350, PB 355, PB 359) — widely planted
* **GT 1** — legacy clone, largely obsolete for new planting but common in older stands
* **Other**
Clones differ in canopy density, wintering timing, and disease susceptibility (notably Corynespora sensitivity on some RRIM 2000 clones), so the phase and wintering windows scale accordingly.
Under **Environment**, choose **Mineral upland**, **Hilly / sloping**, or **Coastal lowland**. The Health tab legend switches to the corresponding band table above.
Enter the **planting date**. The platform derives current stand age and applies the matching age band automatically. Tapping start date can be added later for over-tapping detection.
If a single estate contains blocks across multiple environments (common where a lowland estate extends into hilly reserve), set the environment at the **block** level rather than at the estate level so each block gets the correct band.
## Cross-environment tips
* **Wintering is the single biggest source of false stress alerts on rubber.** Always compare a suspected drop against the same block in previous years before acting.
* NDVI saturates on closed rubber canopies from year 5 – 6 onward. Switch to **NDRE** or **EVI** for stress detection on mature blocks regardless of environment.
* Use **Anomaly** view once one full year of history exists. It adapts to your specific environment and clone. It does **not** adapt to a shift in wintering timing, which is why it is refused inside the wintering window.
* **Over-tapping / tapping panel dryness (TPD)** shows as a slow, block-wide NDVI decline over 1 – 3 years, not a sharp drop. NDRE picks it up earlier than NDVI.
* **White root disease** (*Rigidoporus microporus*) shows as slow, localized NDVI decline in expanding clusters, often starting near old stumps. The most economically important root disease in Malaysian rubber. Cross-check with high-resolution imagery or ground scouting.
* **Corynespora Leaf Fall (CLF)** (*Corynespora cassiicola*) is a major economic disease in Malaysia, especially on susceptible RRIM 2000-series clones. It causes secondary leaf fall **outside** the normal wintering window, so a Feb – Apr dip that fails to fully recover, or an unexpected NDVI drop in mid-year, is a strong CLF signal.
* **Pestalotiopsis / Neopestalotiopsis leaf fall** has emerged as a serious threat across Malaysia, Indonesia, and Thailand since \~2017. Symptoms mimic CLF on satellite (out-of-season leaf fall and delayed recovery). Ground confirmation is required for species-level diagnosis.
* **Powdery mildew** (*Oidium heveae*) attacks refoliation and prolongs the wintering dip by 2 – 4 weeks. A slow recovery after leaf fall is the key signal, most pronounced in northern states (Kedah, Perlis, Perak).
* **Water stress** shows first on **NDWI** and **CWSI**, not NDVI, on closed-canopy blocks. NDVI dips lag water stress by 2 – 4 weeks. Relevant in prolonged dry spells during El Niño years.