Tbilisi Urban Forest

In 2020, the City of Tbilisi initiated a plan to diversify and improve the health of the Mtatsminda Urban forest. The project includes the analysis, design, and replanting of two zones within the larger 700-hectare public Tbilisi Urban Forest: The Narikala Ridge, a north-facing cliffside between the historic city center and National Botanical Garden of Georgia, and Okrokana, to south -facing slope in a peri-urban settlement in the hills above Tbilisi.

The new public forest is grafted into a pine tree monoculture planted in the early Soviet period throughout the city and its surrounding areas. Planting continued through the 1950s-60s, but the plantations are now experiencing infestations of pests and fungi, causing their decline. In contrast to other municipal tree planting projects in Tbilisi, the trees planted in the project were grown in Georgian nurseries.

Ruderal adapted the analytical work of scientific consultants to create detailed spatial plans of coherent patches of plant communities keyed to different soil and slope conditions. These patches include low-growing shrubs and taller trees to provide cover for birds and wildlife and provide a variety of colors, scents, and textures to hikers. The scale and complexity of the urban forest project required innovation in design technology and planting approaches. We developed a custom planting design tool in Grasshopper, a digital modeling software, that allows designers to integrate broad-scale GIS with field-sourced data such as soil depth and composition. These tools produce rapid visualization of the patches at different scales, optimize plant quantities, and allow us to simulate the interaction of diverse species over time.

A year after completion, the irrigation and planting project has jumpstarted a set of nascent plant communities that support a shifting range of biodiverse planted and volunteer species that were suppressed by the former pine canopy.