Smoke, Fire, and the Southern Post Oak Savanna

"Historically, a blanket of bison covered the savanna landscape of southeast Texas.  Large herds consumed vast quantities of grasses and their hooves disturbed the soil, and dispersed seed.  Though the grazing was intense, the bison moved, allowing the savanna time to recover.

Fires regularly spread through the savanna.  These fires were typically very large and continued until stopped by a change in topography or storms smothered them. These fires stimulated growth of the grasses and forbs, suppressed invading woody plants and ultimately contributed to the incredible species diversity of the grasslands." (Houston Wilderness)

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Galveston Island's Family Trees

Lafitte's Cove Nature Preserve in Galveston, Texas. Image via

Performing the work and duties of a landscape architect in coastal communities can be difficult for a number of reasons, chief among them being the possibility - or probability - of sea level rise coupled with infrequent but potentially devastating hurricane activity. In designing the new Sea Scout Base in Galveston, Texas, Studio Outside designers faced the challenge of selecting trees for the site that would be able to withstand not only hard, straight-line winds, but would be adapted to the sandy soils and salty air permeating the beachfront property. 

The site plan called for canopy trees to be planted throughout the property to provide shade, screening from traffic from nearby roads, and to act as a buffer from high winds as well. The challenge was finding a tree that could take all the abuse that the Gulf of Mexico could throw at it, while still performing those essential duties. None of the standard options would work. Most inland canopy tree species were not salt-tolerant enough, and tended to break apart in high level winds. 

Lafitte's Cove Neighborhood in Galveston, Texas

Turns out the solution was located right next door the whole time. 

During a visit to the site, the team heard of a local grove of trees that had survived multiple hurricanes and decided to check it out. In Lafitte's Cove Nature Preserve, a small marshy plot of land in the middle of a neighborhood, the team found a dense copse of coastal live oaks, or sand live oaks, that had withstood the test of time. Quickly, they gathered over a thousand acorns underneath the thick canopy, intent on planting the eventual seedlings on the project site.

From Studio Outside's Paul Freeland:

We collected over 1000 acorns from the trees and had them shipped to Rennerwood Tree Farm to have them custom grown. Two years of careful maintenance, watering and care produced 375 tree saplings 3-4’ tall. These will be planted throughout the site and create a forested perimeter to create an edge to the campus and in the future, screen the traffic of Interstate 45.

Because these trees are propagated from native live oaks that exist on the island, it’s our hope that they stand a better chance of survival over trees that might be from a different part of the country or grown without any exposure to the marine environment they will grow up in.

375 of Galveston's most resilient tree children, grown at Rennerwood Tree Farm

After a little bit of research, I found that  the statistics (pdf) seem to back up the anecdotal evidence of Galveston Island's most hardy tree species. After Hurricane Ivan destroyed much of the tree canopy around Florida's coast, it was the Sand Live Oak (along with the Live Oak) that fared the best, with 99 and 96 percent of the trees surviving the storm, respectively, while pine trees and the tulip poplar fall to the bottom of the list, attaining a less than 50% survival rate.

As designers, we often want to work with materials and methods that we are familiar with, regardless of the location of the project. We strive to be sensitive to the individual needs of the site, but we also carry with us inherent biases towards certain plant types, materials, or design rules depending on where we come from. Galveston's family trees show us that sometimes the answer is right under our noses, on the site itself.

The Sea Scouts, with their new resilient trees, will have a property populated by the most native tree species possible, right from their own backyard. It's what we as landscape architects strive for: to enhance the natural elements of a site, to bring its best qualities front and center. The Sea Scout Base in scheduled for completion in October of this year, and we hope to see those trees standing tall for decades to come.