Oak Savanna Restoration, Part 2

Thursday, November 8, 2012

As I have written in previous posts, four ecological regions converge in Bexar County: Edwards Plateau, Blackland Prairie, Post Oak Savanna and South Texas Plains. Each region has its own characteristics that define the region, but there usually are no clear, well defined boundaries where they converge.

When the Spanish first arrived in what is now Bexar County in the early 1700s and began to establish the Presidio and Missions on the San Antonio River, it appears that most of the area was either riparian woodland along the waterways or some type of savanna in the upland areas.

A savanna is an open grassland with scattered trees. It is a fire based ecology in that the periodic natural occurrence of wildfire is necessary to prevent woody succession from continuing to a full woodland climax.

With permanent human settlement, wildfires were redefined from being a "natural occurrence (or phenomenon)" to being a "natural disaster." Wildfires were suppressed at all cost and the open savanna eventually became woodland.

At the same time that wildfires were being suppressed, periodic flooding along the streams and rivers also destroyed the growing settlements along their banks. To control the floods, the riparian vegetation was removed and the waterways were channelized.

Both the wildfire suppression and the channelization of waterways significantly altered the ecology and habitat of Bexar County. Much has been learned just in the past fifty years about the importance of maintaining healthy ecosystems and the benefits they provide to urban living. Now, numerous agencies within Bexar County are working on major ecosystem restoration projects.

Many of the posts on this blog have covered the major riparian restoration project that the San Antonio River Authority is managing on the San Antonio River. This is the largest restoration project of its kind in the United States. There are plans in the early stages of development to expand this restoration along several of the major tributary creeks of the River.

The San Antonio Parks and Recreation Department is in the early stages of riparian restoration projects at the Medina River Natural Area and along both the Salado Creek and Leon Creek Greenways.

The Texas Parks and Wildlife Department is in the process of a major savanna restoration project in the Frontcountry area of Government Canyon State Natural Area. And the San Antonio Parks and Recreation Department also has savanna restoration projects underway in most of their Natural Area Parks including the project at Hardberger Park pictured in this series of photos.

Which brings me full circle back to my opening statement in Part 1: if you have an interest related to urban ecology and / or ecosystem restoration, Bexar County is the place to be.