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after planting when compared to typical land development practices. Total soil carbon stores are increased in deeper soil regions with Soil Profile Rebuilding. We are currently monitoring soil carbon sequestration, greenhouse gas emissions, soil infiltration and permeability, rooting depth, and a host of other factors to fully characterize the potential of this practice for restoring soils damaged by land development." Dr. Day says, "I can't tell you how many calls I get [from landscape architects, horticulturists, and others] saying, 'I'm trying to get the client to address the soil conditions, but they say it's too expensive.' But then the soil is ignored, and we don't account for the soil when we quantify landscape success." Working with landscape architect colleagues, Day wrote two sets of specs for Soil Profile Rebuilding (SPR) based on the findings at the SRES. She says one is a "friendly spec" designed to simply explain to contractors how to do SPR, and the other is a more aggressive spec that can be used to enforce contracts. Both are protected under a Creative Commons License, meaning that if users of the SPR technique bill themselves as using it, they must follow the SPR specs as written in order to protect the integrity of the technique and the validity of associated research findings. Otherwise, they are free to copy or adapt the specification as needed. Suggestions for improving the specification are welcome. Day says, "Our next step is to expand our installation sites to evaluate SPR in a variety of settings. We are also going to be looking more closely at the stormwater implications of the technique. Currently, we are working with Vincent Verweij and Christine Simpson in Arlington County, Virginia to evaluate SPR in new street medians and sidewalk cutouts, in soil areas that were previously paved. Half the planting areas will receive the SPR treatment and David Mitchell (current graduate student) and I will measure tree growth rate, stormwater infiltration rates, and carbon storage. As we see how things play out in Arlington, the hope is to affect policy to provide incentives for cities to better manage their soils, which is half the battle in attaining the tree canopy we seek. We are also in discussion with Fairfax County, Virginia and hope to have some opportunities to further study SPR there as well." Field research plots at the Virginia Tech Urban Horticulture Center Photo by John James Susan Day's PhD student Yujuan Chen used a device called an Amoozemeter to measure saturated hydraulic conductivity of the different soil profiles in the Soil Profile Rebuilding study. Photo by Velva Groover Dr. Day directs The Urban Horticulture Center (UHC), a "Virginia Tech research facility devoted to developing environmentally sustainable horticulture and urban forestry technology to support the nursery, landscape, and arboriculture industries. The UHC focuses primarily on woody plant research, although some herbaceous production, biofuel feedstock, and vegetable and small fruit trials are located at the Center." www.hort.vt.edu/UHC www.urban-forestry.com This photo illustrates the "scooping and dumping" subsoiling process in Soil Profile Rebuilding. Compost laid on surface is being incorporated 2 feet (.6 m) down with backhoe. Photo by Rachel M. Layman, former MS student who installed plots for the study. 21