INTRODUCTION
Land development is a human activity that has tremendous impacts on the structure and function of the landscape. Those impacts, more often than not, disrupt and degrade natural processes on the site and in adjacent or functionally connected landscapes. The Nature Conservancy has identified habitat degradation due to development as the greatest threat to biodiversity in the United States, partially responsible for the threatened status of 85% of the species that have been identified as such (Stein 2000). In recent decades, development has affected more land than ever before. According to the U.S. EPA, the rate of conversion of land from undeveloped to developed is 2.65 times the rate of population growth in the U.S., a signal of sprawling, land-consumptive development. Not only are more undeveloped sites, or greenfields, being impacted by development, but the impacts appear to be more severe than in previous eras. A recent article in Landscape Architecture Magazine titled “Why Suburbs Will Never Have Tall Trees: Modern Construction Methods Doom Trees Before They’ve Even Been Planted,” makes the observation that older neighborhoods throughout North America appear to provide a suitable environment for tree growth resulting in mature urban forests, while modern-era developments are frequently conspicuous due to the short-lived, stunted, or diseased trees that struggle to survive on these sites ( Kidd 2006).
Modern construction equipment is partly to blame for creating such difficult growing conditions, but, perhaps more importantly, our modern equipment has made it possible to push development further into marginally suitable or just plain unsuitable land. Developers of our continent’s first towns and neighborhoods were limited by the ability of their machinery (or at least the cost-effectiveness of their machinery) to access steep slopes, to move large amounts of earth or to “improve” poorly drained or erodible soils. Today, we can cost-effectively do all of these things, and some of the undeveloped, marginally-suitable land is especially attractive to developers due to its impressive views, acreage, and availability.
With these trends in mind, developers and land planning professionals must seek to lessen the footprint that development leaves on the landscape. Advances in the fields of ecology, geomorphology, and other sciences have given us a deeper understanding of the natural processes that occur in, through, and around any given site. Innovative applications by landscape architects, landscape ecologists, planners, and other design professionals have demonstrated that it is possible to accommodate development in a way that preserves and protects these natural processes. This article will summarize some of the important benefits that healthy natural areas provide, and outline a methodology for low-impact land development.