Alentejo Cork Oak Forests — Live Satellite Health Report

About this region

The Alentejo montado is a savanna-like agroforestry system of cork oak (Quercus suber) and holm oak scattered across the plains of southern Portugal. It is one of the most valuable and threatened ecosystems in Europe — Portugal produces roughly half of the world’s cork. The oaks are stripped of their bark every 9–12 years in a skilled harvest that does not kill the tree if done correctly, making this one of the world’s most remarkable examples of sustainable tree farming.

Climate & growing cycle

The climate is hot Mediterranean with long, dry summers. The oaks are evergreen but drought-stressed — climate change and desertification are a live threat, with dieback episodes becoming more frequent. Summers routinely push temperatures above 38 °C with less than 500 mm of annual rainfall, and the deep-rooted trees depend entirely on winter moisture stored in the soil profile.

Satellite monitoring insights

NDVI runs persistently low (0.2–0.4) on the montado because the canopy is open and the trees are widely spaced. What matters here is the trend: a slow, multi-year decline in NDVI or NDMI signals the montado is dying back — not seasonal variation, but structural decline. NBR is a critical early-warning index for fire risk in the dry grass understory, which can carry flames between the trees during the long summer. Unlike row crops, cork oak health is measured in years, not weeks — making 3–5 year satellite records essential.

Key metrics

Metric	Typical range	What to watch
NDVI	0.2–0.4	Multi-year decline = dieback
NDMI	−0.3 to 0.2	Persistent lows = severe drought stress
NBR	Variable	Drops in understory NBR = rising fire risk

Free report: Get a live satellite health analysis of Alentejo’s cork oak montado this month — see the NDVI trend, fire risk, and moisture status for free, no signup. Check the montado →