sobreiro

Sobreiro, or cork oak (Quercus suber), is an evergreen oak native to the western Mediterranean, with populations concentrated in Portugal and western Spain and extending into southern France and parts of Morocco, Algeria, and Tunisia. It is best known for its thick, corky bark, which is harvested commercially without harming the tree.

Distribution and habitat: Quercus suber thrives on well-drained soils across a range of climates from hot, dry summers to mild, wet winters. It is a key component of montado ecosystems in Portugal and dehesa landscapes in Spain, where it provides shade, stabilizes soil, and supports biodiversity.

Description: The cork oak is a large, long-lived tree. It bears evergreen leaves and develops a deeply fissured trunk covered by thick cork bark. The cork can be stripped periodically for commercial use as soon as the outer bark regenerates, enabling repeated harvests over the tree’s lifetime.

Uses and cork production: The bark is harvested in cycles typically every 9–12 years using careful techniques to avoid harming the tree. Cork is used for wine stoppers, insulation, flooring, and various crafts. Cork harvesting supports rural economies and forest management, encouraging the maintenance of cork oak stands.

Ecology and conservation: Cork oak ecosystems host remarkable biodiversity and contribute to soil and water regulation. Threats include wildfires, land-use change, drought, and pests. Sustainable forestry practices and protected areas help preserve stands. The IUCN Red List generally classifies Quercus suber as Least Concern, noting regional declines but a wide distribution and large population overall.