Transcript of "Landscape Sustainability - University of Nebraska"
G1405 (Revised March 2009) Landscape Sustainability Steven N. Rodie, Extension Landscape Horticulture Specialist Anne M. Streich, Horticulture Educator Functional principles dictate whether the design will This NebGuide describes how to use aesthetic, be usable and will meet certain health and safety criteria. functional and environmentally sound design principles For example drainage must be routed away from the foun , to create a sustainable landscape. dation of a home; sidewalks and outdoor spaces should be sized appropriately for homeowner and visitor use; and “Sustainable landscapes” commonly describes land landscapes should include areas dedicated to private, public,scapes that support environmental quality and conservation and utility needs.of natural resources. For many people, a sustainable landscape is hard to understand or visualize. Other terms such Environmental Design Principlesas xeriscape, native landscape, and environmentally friendlylandscape have been used interchangeably to describe sus Environmental design is the third category of designtainable landscapes. principles. The focus of these principles is to: A well-designed sustainable landscape reflects a highlevel of self-sufficiency. Once established, it should grow 1) enhance landscape microclimate;and mature virtually on its own — as if nature had planted 2) increase biodiversity;it. This self-sufficiency can be difficult to attain, however, 3) reduce resource inputs and resource waste; anddue to the environmental stresses and artificial conditions 4) maximize reuse of resources.placed on plants in urban areas. In addition, many residentsmay not be comfortable with the informality (less plant The diagrams on pages 2 and 3 illustrate how these principlespruning, use of native plants which may lack the desirable can be implemented in a typical residential landscape.aesthetic features of typical landscape plants, etc.) normally Enhance landscape microclimates through:reflected in a sustainable landscape. Adjusting to an informal landscape may take time for • channeling or screening winds;many homeowners, but implementing just one or a few • shading structures and outdoor living areas from theprinciples of sustainable design can significantly benefit summer sun while providing for winter sun exposure;home landscapes. These benefits may include enhanced andlandscape beauty; less environmental decline; more effective • increasing or decreasing humidity (or the perceptionuse of water, pesticides and other chemical resources; more of humidity) through adjustments in air movement.valuable wildlife habitat; and cost savings from reducedmaintenance, labor and resource use. These enhancements can lead to lower energy and water use, healthier plants (which are capable of resisting diseases Aesthetic and Functional Design Principles and insects with less chemical assistance), and more usable outdoor living space. Many design principles typically are reflected in a well- Biodiversity refers to the natural variety of plants, anidesigned landscape. Although sustainable landscapes may mals, fungi, and microorganisms found in all ecosystems.appear more “natural” and less manicured, they still rely Increasing biodiversity, whether in a backyard, neigh orhood bon all of the standard design principles to create a visually park, or along regional creeks, brings many benefits toappealingcombination of plants and materials. landscapes. Aesthetic principles including accent, contrast, har Planting landscapes that more closely reflect nativemony, repetition and unity ensure the design is attractive, plant communities can enhance biodiversity. To achieve this,visually compatible and has a “sense of fit” with the sur developunderstory/overstory vegetation similar to the layerrounding landscape. ing of plants in a natural forest. Biodiversity also assumes (Continued on page 4)
Illustrated Sustainable Design Principles in a Residential Landscape, Part A 1 3 7 5 8 2 6 41. Windbreaks and shelterbelts conserve energy, 5. Grouping similar plants into masses creates a control drifting snow, provide food and shelter for strongervisual impact and interest in the landscape, wild ife, screen unwanted views, filter dust and l copies natural plant community structure, and noise, and create microclimates that benefit plant produces stronger edges in the landscape that are health. important for both aesthetics and habitat.2. Berms (gradually sloped mounds of soil) help 6. Selectively use higher maintenance turfgrasses in definelandscape spaces by creating sloping “walls” areas of high visibility, access, and use. along pathways or between different areas, elevating plants for better visibility, and improving drainage 7. Use lower maintenance turfgrasses and prairie or and growing conditions for plants in poor soil. adapted grasses in areas of low use and access (not necessarily low visibility).3. Ornamental grasses tolerate a wide variety of con ditions, provide food and cover for wildlife and 8. Use organic mulch in all planting beds to increase soil offer year-round visual interest. Many of these water retention, reduce weeds, visually strengthen ornamental grasses are native to the Great Plains. bed lines through the color and texture contrast between the mulch and turf, minimize short-term4. Groundcover plants used on steep slopes eliminate swings in soil temperatures, and enhance soil struc dangerous turf mowing conditions, lessen precipi ture and organic matter content. tation runoff and soil erosion, and provide additional visual interest and biodiversity.
Illustrated Sustainable Design Principles in a Residential Landscape, Part B 17 19 10 13 15 12 14 16 11 18 99. A properly designed, installed and calibrated irri 15. Composting garden waste and applying the resulting gation system minimizes uneven or wasteful water organic matter in the landscape improves growing application. conditions and recycles valuable resources.10. Group plants with similar water needs to avoid 16. Using recycled and/or local-source building over- or under-watering. materials (plastic lumber, prairie fieldstone, etc.) can help develop markets for recycled products,11. Use drip irrigation for shrub beds and other beds to lessen product and installation costs and visually minimize water waste. tie developed landscapes to the character of natural12. Properly select plants for the conditions in which they landscapes. are placed (example: sun and wind exposure, soil 17. Manipulating microclimates by using overhead type and soil moisture conditions). Properly selected vines, shade structures, and trees enhances the liv plants will ensure a healthy landscape with minimal ability of outdoor spaces. need for chemicals or additional management. 18. Raised beds improve access to plants, make it easier13. Landscape “vertically” as nature does. Placing small to manage the soil, and improve growing conditions plants and groundcovers under small trees under by increasing soil aeration and drainage. large trees enhances both visual and biological diversity. 19. Where feasible, use plantings to connect developed landscapes with natural landscape areas. These14. Creating wildlife habitat draws birds and other ani integrated landscapes are considered more envi mals, which add to the aesthetics of the landscape ronmentally valuable than small, scattered areas and offer biological control of unwanted insects. of vegetation.