From Invasive Trees To Free Material For Low-Carbon Construction

While cities across the country are mandating zero-carbon footprints for new public buildings, designers and manufacturers are looking for new, ecology-positive building materials.

Katie MacDonald and Kyle Schumann, founders of After Architecture, have set their sights on invasive species, which are often byproducts of sustainable forestry and ecological restoration efforts.

According to Architect Magazine, invasive species are plants that can cause an imbalance in local food webs, displace indigenous species, and reduce biodiversity.

“By developing architectural uses for nonnative species and timber thinnings—specimens that are strategically removed as part of forest management—MacDonald and Schumann believe the building industry can wean off carbon-intensive materials, such as concrete, steel, and aluminum while creating mutually beneficial supply chains.”

Last year, MacDonald and Schumann explored the use of regional invasive species as building material at the University of Tennessee, Knoxville. 

As a part of the project, UT students used fallen branches of Bradford pear trees, a nonnative ornamental species, to develop a lattice-like architectural system using natural branch curvature as the design model.

Other groups of students used kudzu, albizia, and bamboo plants to build walkway railings, and an affordable house prototype inspired by Polynesian dwellings.

One thing is certain — using invasive plants for construction will require close cooperation among agencies that oversee natural resources and select the materials.