Oak savanna
[5] The oak savannas of the Midwestern United States form a transition zone between the moist broadleaf and mixed forests to the east and the arid Great Plains to the west.
Savannas normally were found next to large prairies near rolling hills and this combination of habitat was perfect for deer, bison, elk, and other grazing animals.
Research by Granado-Díaz, Villanueva, & Colombo (2024)[12] on land manager preferences for environmental services in oak savannas offers historical insights into the evolution of conservation strategies.
This study illuminates the critical role of managing understory vegetation for ecological health, integrating seamlessly with the natural fire regimes that shaped these ecosystems.
These findings underscore the importance of preserving the intricate balance between fire, vegetation, and wildlife that defines the oak savanna's unique ecological identity.
Low intensity, Spring-time prescribed burns have been used since 1964 at the Cedar Creek Ecosystem Science Reserve in Minnesota in an attempt to restore the area to an oak savanna.
This insight is pivotal, as it highlights the interconnectedness of all elements within the oak savanna ecosystem, emphasizing that successful restoration efforts must account for the complexity of biological relationships.
Historical records, such as French ordinances dating back to the 13th century, illustrate early recognition of obstacles to oak regeneration.
[23] Pre-settlement there were approximately 50,000,000 acres of oak savanna in what is now the Midwestern United States, all of it located exclusively in a wide strip stretching from southwestern Michigan to eastern Nebraska, and from southern Manitoba to central Texas.
After Europeans arrived, fire suppression and settlement diminished the oak savannas to a fraction of their former expanse; they currently exist in many fragmented pockets throughout their native range.
Valadi et al. have explored the conflicting edge influences on herbaceous species in oak savannas, shedding light on the complex interactions that impact the distribution and conservation status of these ecosystems today.
[24] This research underscores the need for nuanced conservation strategies that address both the macro and microecological pressures impacting oak savanna preservation.
[22] It is estimated that about only less than 0.02% of the original savannas remain due to human interaction and many organizations and conservations are prioritizing restoring and recreating these ecosystems in the midwest.
However, according to proponents of the controversial wood-pasture hypothesis, they can be viewed as functional analogs to the oak savannas that may have naturally covered large parts of Europe during the early Holocene.
[29] In the Western Mediterranean, oak savannas, known as dehesas in Spanish and montados in Portuguese, are at present widespread, concentrated in Southern Portugal, the Extremadura and Andalusia.
