An oak savanna is a type of savanna—or lightly forested grassland—where oaks are the dominant trees. The terms "oakery" or "woodlands" are also used commonly, though the former is more prevalent when referencing the Mediterranean area. These savannas were maintained historically through wildfires set by lightning, humans, grazing, low precipitation, and/or poor soil.
Oak savanna, California
Wisconsin bur oak savanna in mid-summer
Fox River Grove, Illinois oak savanna; winter
Fire-tolerant bur oak savanna in Wisconsin hill country
A savanna or savannah is a mixed woodland-grassland ecosystem characterised by the trees being sufficiently widely spaced so that the canopy does not close. The open canopy allows sufficient light to reach the ground to support an unbroken herbaceous layer consisting primarily of grasses. According to Britannica, there exists four savanna forms; savanna woodland where trees and shrubs form a light canopy, tree savanna with scattered trees and shrubs, shrub savanna with distributed shrubs, and grass savanna where trees and shrubs are mostly nonexistent.
A tree savanna in Tanzania, East Africa (Tarangire National Park)
A grass savannah in South Africa (Kruger National Park)
A savanna woodland in Northern Australia demonstrating the regular tree spacing characteristic of some savannas.
Bushfire in Kakadu National Park, Australia
