The wild olive, scientifically known as Olea europaea subsp. europaea var. sylvestris, is the undomesticated ancestor of familiar olives found in stores today. It is the original form of the olive tree, evolving naturally without human intervention. This ancient lineage has been in the Mediterranean Basin for millennia, long before cultivation began. It is the genetic foundation for all modern olive varieties, emerging through selective breeding.
Characteristics and Habitat
The wild olive tree is often a scraggly, shrub-like plant, smaller than its cultivated counterparts, growing 8-15 meters tall, with frequently thornier branches. Its leaves are generally smaller and more leathery, with a darker green upper surface and a silvery-grey underside, helping it reflect sunlight and conserve water in arid environments. The fruit is notably smaller than commercial varieties, with a significantly higher pit-to-flesh ratio, meaning less edible pulp surrounds a large stone.
These plants thrive in the Mediterranean Basin, a region with hot, dry summers and mild, rainy winters. Wild olives adapt well to harsh conditions, found in rocky, arid landscapes, and on poor soils where cultivated varieties struggle. They are common in maquis and garrigue scrub formations, showing resilience to drought and salinity stress.
Relationship to Cultivated Olives
All cultivated olive varieties originated from the wild olive through centuries of human selective breeding. This domestication process began around 6,000 years ago, involving intentional propagation of trees with desirable traits. Humans favored olives that produced larger fruit, more flesh, and higher oil content, making them efficient for food and oil production.
Cultivated olives were also selected for reduced bitterness, linked to the concentration of certain compounds. Morphological changes, such as increased fruit size and flesh, resulted directly from agricultural intervention aimed at maximizing yield and palatability. This long process of selection created distinct genetic and phenotypic differences between wild and domesticated forms, though some genetic overlap persists due to cross-pollination.
Preparing Wild Olives for Eating
Wild olives are intensely bitter when picked, due to a high concentration of oleuropein, a compound found in their skins and flesh. This bitterness makes them inedible without processing. To make them palatable, “curing” is necessary, which leaches out the oleuropein and other harsh-tasting compounds.
Common curing methods include brining or water curing. In water curing, olives are typically cut or cracked to allow the bitter compounds to leach out more easily, then soaked in fresh water changed daily for a week or more. Brining involves fermenting olives in a saltwater solution, which can take several months to a year, during which lactic acid bacteria break down oleuropein and convert natural sugars. While labor-intensive and yielding smaller quantities compared to commercial olives, properly cured wild olives offer a unique, robust flavor profile distinct from their cultivated counterparts.