Degradation of water quality in urbanizing watersheds due to increased impervious surfaces and removal of natural vegetation and wetlands is well recognized. What is under-appreciated, however, is the conflict between ornamental landscaping practices in urban/suburban ecosystems and water quality management. A landscaping paradigm that views plants only as ornaments has dominated over the past century, resulting in the replacement of native plant communities with expansive lawns sparsely accented by plants that evolved in Asia, Europe, or South America (McKinney 2006, Standley 2003, De Candido et al. 2004). As of 2004, lawns occupied more than 164,000 sq km in the U.S. (8 times the size of New Jersey) (Milesi et al. 2005). At the predicted growth rate of 1554 sq km per year (Robins & Birkenholtz 2003), lawns will have replaced native plant communities in over 182,000 sq km by 2011. Manicured lawns have been a long-standing status symbol for wealth, character, and stewardship in Western societies (Kolbert 2008), but this approach to landscaping has converted on average 92% of landscaped areas to turf grass and has reduced the biomass of woody plants in suburbia by 90% compared to that found in mature eastern deciduous forests (Tallamy et al. Submitted).
Because plants are the mechanism by which water is cleaned and stored, carbon is sequestered and stored, and complex, stable food-webs are created and maintained, any reduction in plant abundance and diversity is a reduction in the production of vital ecosystem services. This is highlighted by recent research that shows that ecosystems with higher biodiversity do a much better job in removing nutrients and improving water quality, as well as sequestering carbon (Tilman et al. 2006, Cardinale 2011). So much area in the U.S. has been converted to a matrix of urban and suburban centers, particularly near major rivers, bays and coastal zones, that we can no longer rely on marginalized “natural” or targeted "buffer zones" alone to provide the quantity and quality of water and other ecosystem services required by large human populations. This problem is especially illustrated in the Chesapeake Bay Watershed where water quality gains made by implementing miles of riparian buffers continue to be undercut by nutrient inputs from lawn fertilizers in expanding suburban communities (Law et al. 2004). Such a model of watershed management is unsustainable and indefensible and we must revise our existing land management practices so that water quality and ecosystem services are maintained in all managed ecosystems.
With this project, we propose to measure the magnitude of water quality improvement that be attained by changing our current lawn-based landscaping paradigm to one that encourages less-intensive management and allows for a greater abundance and diversity of native flora and fauna. Management practices that could provide such benefits and services include converting areas now in lawn into attractively designed thickets of trees and shrubs; allowing other areas to become managed meadows; reducing mowing, fertilizing, herbiciding and irrigation schedules on areas that will remain lawn; and creating rain gardens in areas of high storm water runoff. The goal of this proposal is to demonstrate the value and feasibility of such innovative watershed management practices by quantifying the improvement in water quality and ecosystem services through their implementation. We believe ecological and economic analyses of the benefits associated with our approach to water quality management at the watershed scale as well as demonstration sites in actual residential watersheds will help inform the public about the vital roles urban landscapes play in maintaining the ecological integrity of urban ecosystems. We will accomplish this by -
- quantifying the ecological and economic benefits to water quality and infiltration, as well as the production of other ecosystem services that result from increasing the biomass, productivity, and diversity of plants in urbanizing watersheds (research component)
- producing nationally marketed educational videos to train watershed managers, landscape professionals (practitioners, designers, and architects), land owners, the nursery trade, and public officials about the critical functions of plants in watershed management, as well as mentoring undergraduate student projects and opening our research sites to public tours (education component)
- developing an ecosystem services brochure for public consumption; posting recommendations on a sustainable landscaping website; writing popular press articles about landscape practices that improve water quality; producing interpretative signage to explain landscaping practices at our study sites; conducting tours for homeowners and landscape professionals to demonstrate water quality landscaping practices; presenting landscaping short courses for homeowners, Master Gardeners and landscape professionals; and developing nationally distributed science modules to teach youth and land owners how to generate ecosystem services at home (outreach component).
We will conduct this study at Winterthur Museum, Garden and Library (WMGL), an 809 ha public garden located in northern Delaware. This site provides the opportunity to compare water quality management strategies in several contiguous, multi-hectare watersheds in which separate streams are impacted by traditionally mowed landscape areas or by sustainably managed landscapes (meadows, forests and landscape beds). The garden receives 116,000 visitors per year, providing built-in opportunities for public education at the study site through permanent interpretive signage, workshops, and expert-guided tours. We will also manipulate Applecross, a suburban development adjacent to Winterthur. Applecross, was built using bioswales and meadow corridors to buffer nearby streams. By working directly with several homeowners to develop demonstration sites on their properties, we will provide examples of how sustainable landscapes can be created and managed to improve water quality and other ecosystem services without losing aesthetic appeal. The proximity to Winterthur and the existing focus on water quality make Applecross an ideal suburban development to demonstrate sustainable landscaping concepts on a suburban lot scale.
To conduct this innovative study we bring together a strong, interdisciplinary team of scientists and economists. Dr. Inamdar, an expert in watershed water quality and hydrology, has evaluated water quality for multiple USDA-funded watershed projects and will evaluate the changes in water quality in this study as a result of the management practices. Dr. Duke is an environmental economist who studies problems at the land/water interface. His work includes studies of the supply side of ecosystem services (landowner behavior) as well as the demand side (public values associated with enhanced protection). Dr. Tallamy, an insect ecologist, has been quantifying the impact of non-native ornamental plants of food webs in urban ecosystems for the past decade with USDA and NSF support. He is now expanding his work to compare the ecosystem services provided by different landscaping approaches. Dr. Bruck is a professor of landscape design who maintains a private practice in residential landscape design. In both her teaching and practice, she employs sustainable landscape management techniques in aesthetically pleasing designs. Dr. Barton is an extension specialist in horticulture who has worked on sustainable landscaping practices throughout her career, including a 13+ yr collaboration with the Delaware Department of Transportation to research and implement sustainable roadside vegetation practices. Our collaboration has already proven to be synergistic and is highly convenient; all PIs are in the same college and can meet in person frequently and on short notice to coordinate activities.
Water quantity and quality challenges in urbanizing watersheds
Urbanization represents a significant threat to the environmental quality of terrestrial and aquatic ecosystems. Urban development results in degradation of water quality of streams, lakes, and other water bodies that drain these landscapes (Paul and Meyer, 2001). More than 13,000 km of stream and rivers are considered impaired because of urbanization (USEPA, 2000). Increase in impervious surface area, removal of natural vegetative zones and wetlands, and chemical inputs associated with lawns, golf courses, storm sewers, and wastewater treatment plants are some of the key factors contributing to environmental degradation in urban ecosystems. The impacts of urban development on stream water quality and associated ecosystem processes are synthesized in Table 1.
Management practices and their impacts on water quality
Environmental impacts of lawns on water quality
Manicured, weed-free lawns have become the dominant residential status symbol of our times. Achieving this ideal, however, is both economically and ecologically costly, particularly in terms of water conservation and quality. Lawns remain weed-free because they are treated with 7lbs of broadleaf herbicide per application per acre, as much as 78 million lbs of pesticide nation-wide. For perspective, this is a rate of pesticide use 3.5-10 times higher than applications to agricultural crops (EPA 2005, National Audubon Society 2008). Herbicides are not the only threat from lawn care to water quality. It is estimated that each year more than 17 million gallons of fuel are spilled during refueling of power lawn equipment (NYS Dept. of Env. Cons. 2011).
Table 1: Impacts of urbanization on water quantity, quality, and associated ecosystem processes in streams (derived from a review by Paul & Meyer, 2001)
|Component||Impacts of urbanization on streams|
|Hydrology||Decreased infiltration and thus reduced groundwater recharge and lower stream baseflow (Barringer et al., 1994)|
|Shortened lag time in storm runoff and increased peak stream discharges (Hirsch et al., 1990); greater variability in stream runoff and greater changes in flow regime; greater proportion of surface runoff than groundwater constituting stream water (Epsey et al., 1965)|
|Stream water temperature increase due to heating effect of impervious surfaces (Pluhowski, 1970)|
|Geomorphology||Decreased drainage density as streams and channels are paved over or buried (Meyer & Wallace, 2001)|
|Increased bankfull discharges as peak runoff increases (Dunne & Leopold, 1978)|
|More sediment in stream runoff (Wolman, 1967)|
|Initially streams aggrade with sediment followed by an erosive regime that increases stream incision and increases channel depths (Dunne & Leopold, 1978)|
|Sinuosity of streams decrease as channels are straightened to carry more runoff; changes in pool-riffle regimes (Arnold et al., 1982)|
|Water Quality||Increased input of phosphorus and nitrogen from lawn fertilizers, WWTP, sewers, etc. Particulate P input especially increases (Omernik, 1976; Smart et al., 1985)|
|Other ions such as calcium, sodium, potassium, and magnesium also increase. Road salts increases the chloride content of stream waters. The increase in all ions increases the conductivity of runoff waters (McConnell, 1980; Smart et al., 1985; Herlihy et al., 1998)|
|Increase in metals such as zinc, chromium, copper, nickel and cadmium in runoff (Wilbur & Hunter, 1979)|
|Increased pesticides in runoff waters due to application on lawns, golf courses, etc. (Schueler, 1994)|
|Biological and ecological effects||Increased bacterial densities in stream runoff from sewers and WWTPs (Duda et al., 1982)|
|Nutrients increase algae biomass but lower diversity (Chessman et al., 1999)|
|Decreased abundance and diversity of macrophytes, invertebrates, and fish in streams; tolerant taxa increase (Resh & Grodhaus, 1983, Onorato et al., 2000; Gafny et al., 2000, Suren, 2000;)|
|Ecosystem processes and services||Particulate organic matter increases, and dissolved organic matter inputs are more labile (Sloane-Richey et al., 1981); organic matter processing and retention in urban streams is lower (Paul, 1999)|
|Higher gross primary productivity and community respiration (Ball et al., 1973)|
|Decreased ability to consume nutrients; buffering ability of stream ecosystems is decreased in urban environments (Pollock & Meyer, 2001)|
Our research, educational approaches, and outreach efforts will help convey the message nationwide that we can no longer exempt such landscapes from contributing to functional ecosystems. Homeowners, landscape designers, architects and managers, and the horticultural industry control local water quality but do not know it. These groups have little understanding of the relationship between diverse plant communities and the availability of clean water nor about how easily watershed management could be improved by incorporating more plants into the landscapes they control. Our project will address this problem and provide viable alternatives and mechanisms for improving water quality through sustainable landscaping practices. We will communicate with stakeholders who make policy decisions about landscape management regulations, professionals in the nursery and landscape industry, greening organizations in major cities promoting tree planting, and conservation organizations promoting wildlife habitat. The data we collect on water quality and other ecosystem services and the landscape demonstrations we photograph will inform stakeholders about the value of replanting watersheds and will help these stakeholders promote the widespread adoption of alternatives to mowed turf landscapes (Fig 1).
Site location and description
This study will be conducted on the property owned by WMGL in New Castle County, Delaware (39o 48’ N, 75o 36’ W). This landscape is drained by the subwatersheds of Clenny Run which eventually drains into the Brandywine Creek. The predominant soil type in the watershed is Glenelg and Manor loams. Average annual precipitation for New Castle County is 1130 mm with highest monthly precipitation typically occurring in August (USDA-SCS, 1970). Precipitation during the summer is associated with low-pressure systems from the south which produce high-intensity convective storm events. Average annual temperature is 54oF (12oC) with maximum temperatures typically occurring during the latter part of July.
This site was selected because: a) it provided large land parcels with desired practices (intensively mowed lawn versus meadows) which were nicely contained within sub-watersheds that could be sampled easily at stream outlets; b) the site was close to the campus of University of Delaware – hence, easily accessible for students for sampling during storm events; c) the property owners provided permission for our research and were excited about participating in our research program; d) detailed information about land management practices is available from the Winterthur grounds crew; e) detailed data on GIS is available for the site which includes LIDAR DEM, aerial photos, stream tributaries, and SSURGO soils maps; and f) historic water quality data is available from previous investigations; g) as a public garden, WMGL provides many opportunities for education and outreach.
Watershed-scale water quality monitoring design and data collection:
The primary intent of our water-monitoring program is to investigate water quality differences between streams draining intensively managed lawns and intermittently managed meadows. In addition, we will compare watersheds with forests and impervious surfaces such as parking lots, roads and buildings, other land covers typical of urbanizing watersheds. To quantify differences in water quality we will sample and monitor six distinct but contiguous watersheds identified through field-surveys as well as GIS delineation of tributaries, land-use, and watershed boundaries from a 10m DEM (Fig 2). All of these watersheds are similar to each other in area, and are also similar with respect to geology, soils, and topography. Watershed W4 (15 ha) will be our primary “traditionally-mowed lawn” watershed treatment (this watershed is completely in this land cover treatment). Existing mowing, fertilization and weed control practices employed by WMGL will be supplemented to closely estimate lawn management practices for a typical residential lawn in W4. Watershed W3 (12 ha) will represent the “intermittently-managed native meadow site” (only a small portion of this watershed has trees with remaining land in meadows). In addition to these two watersheds we will also sample runoff from watersheds W1 (19.1 ha), W2 (13.4 ha), W5 (37.9 ha), W6 (22 ha) (Fig 1). Watershed W1 has the largest areal extent of impervious area (parking lot and buildings) and will represent the watershed with greatest urban impact. Watersheds W2 and W5 have large proportions of forest cover and thus would be expected to best represent natural “background” water quality conditions at this study site. Watershed W6 includes an intensively managed golf course at its upper end and thus represents a landscape that is partially under intensive management. Exact percentages of land cover will be determined and mapped for all the six watersheds using GIS.
Water quantity and quality monitoring and sampling will be conducted using a combination of two approaches: (1) continuous monitoring and (2) synoptic sampling. Continuous water monitoring will be performed on the two main treatment watersheds – W4 (traditional lawn) and W3 (native meadow). This will include continuous stream discharge monitoring and continuous recording of stream-water physiochemical parameters at the outlet of the streams draining the watersheds. Stream discharge will be determined by measurement of stream stage (every 20 minutes) and a calibration curve that relates stage to discharge. Physiochemical stream water parameters will be recorded using continuously-logging (every 20 minutes) water quality sondes (In-Situ Inc.) that will be positioned in stream water at the outlet of these watersheds. The sondes will record: stream water depth, pH, dissolved oxygen, specific conductivity, temperature, and turbidity. We will use the continuously-recorded sonde-turbidity as a measure of suspended sediment after developing a regression relationship between manually-sampled suspended sediment concentrations and sonde turbidity values.
All samples will be analyzed for: total nitrogen (N), nitrate-N, ammonium-N, dissolved organic N (by difference), total phosphorus, ortho-phosphorus, silica, dissolved organic carbon (DOC), sodium, sulfate, chloride, magnesium, and potassium. A few selected samples will also be analyzed for 2, 4-D amine (most commonly used broadleaf lawn herbicide), oxadiazon and dithiopyr (commonly used preemergent lawn herbicides). Water analyses will be performed by the certified University of Delaware Soil and Water Services laboratory located on campus.
In addition to these routine analyses, we will analyze selected water samples by ultra-violet and fluorescence spectroscopy (Fellman et al., 2010; Weishaar et al., 2003). These optical methods provide insight into the potential bioavailability of dissolved organic matter (DOM) for the aquatic food web. We will perform the UV and fluorescence analyses following standard protocols described in Inamdar et al. (2011a, b). Quality of DOM will be characterized using specific UV absorbance (SUVA) and 250nm, absorption coefficient a254, humification index (HIX), fluorescence index (FI), spectral slope ratio SR and protein-like fluorescence (Inamdar et al., 2011a). - Since one of our hypotheses is that landscapes planted in meadows or woody species will enhance biodiversity, we will also use standard stream monitoring protocols in March and October to measure the species richness and abundance of aquatic invertebrates in each stream. All water quality data collected from the treatment watersheds will be analyzed using standard statistical techniques (such as ANOVA, principal component analyses, etc.) to investigate the differences in the treatments.
Comparing resident biodiversity
We will use three taxa [plants, Lepidoptera (moths and butterflies), and breeding birds] as surrogates for total biodiversity when comparing the impact of landscape vegetation on watershed biodiversity. We will use line-intercept sampling to estimate vegetation cover, biomass, and structure as a measure of the overall composition of vegetation cover (Krebs 1999). We will compare vegetation structure between watersheds by measuring the total percentage of plant cover at 4 height strata (5 cm, 1 m, 4 m, >15 m) along 5 transects equally spaced across each watershed. We will record the length of each transect intercepted by each species at the 4 height strata. Areas of the transect with a cover of multiple species (e.g., a meadow or mowed lawn) will be divided into “communities” in which the cover and plant species composition remain relatively consistent. We will categorize each species in these communities as a dominant, average, or rare member of that community and then assign that species a value for percent cover of the transect line based on its dominance category and number of species present in that community. Once each month from May- September we will use a total search approach (Wagner 2005) to quantify Lepidoptera larvae every 10 meters along each transect. At each sample point along the transect, on days with no rain, we will record all caterpillars on all twigs and vegetation within reach and inside a circle defining a vertical cylinder with a 0.5-m radius between 09:00 and 14:00 and identify each individual to species or morphospecies.
We will estimate breeding-bird species richness with 25-m fixed-radius point counts (Donnelly & Marzluff 2004). Sampling points will be selected with orthophotos to maximize the number of points in each watershed while maintaining a 25-m buffer between adjacent circles to minimize double counting of birds. Avian counts will be collected between 05:00 and 07:00 five times in each watershed between 15 May through 7 July as this is the primary period of breeding activity at our study site. We will record all native birds seen or heard within the 25-m radius plot for a 5-minute interval. Birds flying above the canopy within the radius will not be included. We will also record birds actively breeding on a site by locating a nest, observing transport of nesting material or food, or observing fledglings. We will estimate avian abundance at each site by summing the maximum number of individuals detected across the point counts for each species and dividing it by the number of points sampled on a property. All estimates and comparisons will be made with the watershed as the sampling unit (n = 6) and compared by ANOVA.
Comparing pollinator communities
The abundance and richness of nesting pollinators will be compared each year of the project among our six watersheds by counting reproducing pollinators along 10 1m wide transects that are evenly spaced across each watershed. This approach will enable us to assess both population size and species richness of ground-nesting bees (nest holes of Halictidae - sweat bees, Andrenidae - andrenid bees, Megachilidae - leaf-cutting bees, and Bombinae - bumble bees) and butterflies in each watershed expressed as mean nests (bees) or larvae/pupae (butterflies) per linear meter. Butterflies will be quantified by searching all host plants located within each transect and counting all larvae and pupae on them. Transects will be quantified once a month from April to September and a seasonal species total and abundance will be generated for each transect. Watersheds will be compared by Oneway ANOVA. We will not assess bees or butterflies at flowers because we are interested in the pollinators that are reproducing within each watershed. A pollinator at a flower could be using resources outside the watershed for reproduction.
Quantifying pest control services
We will compare the natural enemy community in each watershed in three ways. First, we will measure the abundance and diversity of Icneumonid and Braconid parasitoid wasps and insectivorous birds, insectivores that will serve as surrogates for the entire community of natural enemies. Icneumonids and braconids parasitize caterpillars and herbivorous beetles and their diversity and abundance is a good indicator of natural enemies in general. Once each month from May-September we will use sweep netting to sample target parasitoids along the transects established for vegetation surveys (see Comparing resident biodiversity). Controlling for sweeper, we will take 25 sweeps every 20 m, store samples in 70% ethanol and identify Ichneumonids and Braconids to morpho-species in the lab and, expressing the data as parasitoids per meter, compare by ANOVA among watersheds.
We also will plant 10 evenly spaced 5’ sentinel black cherry trees in each watershed. We will infest 5 trees in years 2 & 3 of the study with 20 neonate common bagworm (Thyridopteryx ephemeraeformis) larvae as they hatch in May and record viable adults on each tree in March of the following year. Bagworms are major pests of ornamental plantings but are controlled by ichneumonid wasps, chickadees and titmice. Bagworm survivorship will be compared among watersheds by ANOVA after log transforming the data. On the remaining 5 cherry trees in each watershed we will record mean percent leaf damage in September by estimating the percentage of each leaf eaten by mandibulate and haustellate insects on 4 branches chest high in each of the 4 cardinal directions. Finally, the densit of breeding insectivorous birds will be estimated in each watershed as described above.
Estimating carbon sequestration
Measuring the ability of different types of vegetation to sequester carbon has been controversial, particularly for turf grass measurements (Townsend & Czimczik, 2010). At issue is the rate at which C02 is stored in plant biomass above-ground, in plant biomass below-ground, and in organic matter in soils, as countered by C02 emissions from landscape maintenance. The product of C02 sequestration is carbon stored within plant material over time. Although results vary, particularly with plant diversity (Tilman et al. 2006), there is evidence that below-ground sequestration rates are similar in various types of plant communities (Pouyat et al. 2009). What differs substantially, and what we will compare among our watersheds, is the amount of carbon stored in above-ground plant biomass. Because 1kg of plant biomass dry weight equals 0.45kg carbon built from 1.65kg atmospheric CO2 (http://www.docstoc.com/docs/32884529/Trees-and-Carbon), it is easy to estimate carbon stored by different landscaping practices. A new web product by the U.S. Forest Service called Tree Carbon Calculator (http://www.fs.fed.us/ccrc/topics/urban-forests/ctcc/) provides a convenient, species-specific estimation of stored carbon in trees using DBH as the single input. We will use this estimate on all standing and downed trees in each watershed. To estimate non-tree biomass (turf grass, meadow, forest floor) we will remove, dry and weigh all vegetation and litter to mineral soil level within ten randomly selected 0.5m quadrats in each cover type. We will then estimate from orthophotos the area in meters within each watershed allocated to turf, meadow, and forest and estimate and compare by ANOVA total above-ground carbon stored within each watershed.
Economic assessment of landscape practices
The economics of landowner property management choices involve four aspects: (1) the knowledge of the benefits and costs of each management practice; (2) the actual costs to the landowners of implementing practices; (3) the private benefits to the landowners of implementing practices; and (4) the received benefits and costs by neighbors. The research, education, and outreach components of this proposal address the first aspect in detail. This subsection discusses how the second aspect will be addressed and also suggests ways the PIs plan to extend this work to the third and fourth aspects in a related research proposal.
Cost data will be collected during all facets of the research implementation. Three major land treatment types will be compared during the three-year project. The treatments include routinely mowed turf (one mow/week); meadows (one mow/year); and, forests (established cover of trees, shrubs and ground layer). For each treatment, the full facet of fixed and variable costs, including material and labor (M&L), for each activity will be collected. The cost data will be collected or estimated for both installation and sustainable management. Examples of installation costs include the M&L associated with site preparation, plant and establishment materials, and planting costs. For continued management, costs will include mowing, fertilization, irrigation, and weed control. In addition, costs will be calculated at varying scales, including a one-acre, large-scale management and a 1,000-square-feet basis for homeowners. Costs will be calculated at the time of occurrence (i.e. planting a meadow will have a high initial expense compared to establishing a lawn), and brought into present value for comparison. This allows one to determine whether there are long term savings of vegetation that requires less routine management once it becomes established. We will also calculate the difference between measures taken to establish each land treatment. Aggressive establishment (i.e. planting a forest or a meadow) may yield different overall costs when compared to passive establishment (i.e., allowing succession to occur naturally resulting in stable meadow or forested land treatments).
It is anticipated that our proposed research effort will be further leveraged through another grant proposal to a different agency to support a second economic study at this site on the benefits to landowners implementing practices and to neighbors. Briefly, this effort would involve a choice experiment (choice model), which is an experimentally designed survey technique producing data estimated with a mixed logit regression technique that measures the marginal benefits associated with changes in public goods. For instance, this survey would allow one to estimate the benefits to a landowner and neighbors of a change from turf to native shrubs on 20 percent of the landowner’s parcel. Indeed, the benefits of any marginal change in ecosystem services can be estimated with this technique and, further, the benefits can be parsed into water quality, aesthetic, habitat, and other benefits. Dr. Duke has conducted numerous research projects using this technique.
Researchers will develop three major educational products including a video, science curriculum and sample designs for professional designers and homeowners.
Documentary-style Video – Acceptance of non-traditional landscapes has been found to be much greater when people receive information about the benefits of non-traditional management. Online survey respondents were much more accepting of infrequently mowed turf on the roadside after viewing a 6-minute video explaining the water quality and other ecosystem services provided by the meadow land treatment (Lucey & Barton, 2011). We will produce a high quality 15-minute video explaining and illustrating the water quality and other ecosystem services provided by each land treatment based on data collected. Video and still pictures taken at the various landscape treatment sites will be used to create the narrated video.
Clean Water Curricula - UD students enrolled in PLSC 390, Student of Our Environment, an honors colloquia for freshman, will collect water quality data at the stream monitoring sites at WMGL and use this experience to create middle school science curricula. Four groups of five students will each work with one middle school teacher from four different Delaware schools and a Delaware Master Gardener to establish high quality curriculum. PLSC 390 is taught at UD every fall semester beginning in 2010 and will focus its curriculum development project on the water monitoring sites in 2013 and 2014, resulting in the development of 8 curricula for use in schools.
Sustainable Suburban Landscapes Samples– UD students enrolled in PLSC 232, Basic Landscape Design an undergraduate course focusing on innovative environmental problem solving will create sample suburban landscape plans to demonstrate best management techniques. Students will work in teams of three, using existing properties and actual clients from Applecross development, to develop sample plans to demonstrate creative reduction of lawn areas by 50%, increase in tree cover by 100%, increase in plant diversity by 100% and on site retention and filtration of 90% of the rain predicted in one year in Delaware. These sample landscape plans will be presented to a panel of professionals, refined, and posted to the University of Delaware Botanic Garden’s (UDBG) Sustainable Landscape Website. This site will promote the landscape plans as best management examples that can be used by homeowners throughout the country.
Evaluation: The effectiveness of these educational tools will be evaluated through web monitoring that reveals the number of times the video is requested and shown, as well as site visitation to relevant areas of the websites. In addition, student evaluations, professional assessment, and feedback from students and teachers utilizing the middle school curricula in the year following their development will provide an evaluation of the tools’ educational effectiveness.
Outreach and Extension
Outreach will focus on two groups of stakeholders – homeowners and landscape industry professionals. Managing fundamental change requires all parties to have vested interest in the outcomes and/or a deep understanding of the intrinsic benefits. Homeowners educated in non-traditional landscape management practices may demand a different type of maintenance from their landscape professionals. Those professionals should then be prepared and skilled in non-traditional management techniques.
Interpretive Signage: Awareness of different land management styles may occur when a homeowner sees his or her neighbors utilizing non-traditional landscape management techniques. However, interpretive signage will raise awareness of the benefits as well as the acceptance of specific landscape management practices (Saksa & Barton, 2011). Demonstration sites; therefore, will be accompanied by interpretive signage to explain the environmental benefits of our treatment sites. Signs, consistent with the existing style of interpretation, will be created, produced and installed in key locations at WMGL (figure xx). Placement in high visibility areas nearby treatment sites, including tram stop locations as well as sites frequented by walking garden visitors, will be necessary to achieve outreach goals. Signs will be permanent and extend the outreach of this project far beyond the end of the grant for the 116,000 yearly visitors to WMGL. Researchers will develop and install temporary signs to highlight the water monitoring locations. These signs, which will be updated yearly to include water quality data collected at the site, will provide a simple explanation of monitoring techniques. The signs will be visible to casual walkers who are members of WMGL as well as by participants in organized tours of the project.
Demonstration site(s) in Applecross: Two homeowners living in a 2005 Greenville, DE development, Applecross, will be solicited to participate as demonstration sites. This site was selected by the research team because of its proximity to the WMGL test site as well as the size and character of the 22 residential properties in the sub-division. At Applecross, the builder and developer believed in working with the existing topography of the site (http://www.applecrossgreenville.com/developer.php). The existing vegetated swales and meadow buffers will provide context for the non-traditional landscape and allow these landscapes to blend into their surroundings.
We will design and install sustainable landscape features including reduced lawn areas, meadows, reforested zones, and rain gardens. Recognizing that mowed turf is a useful groundcover for human-centered activities, each site will maintain a small area of useful mowed turf for circulation, play, and entertaining. These landscapes will be designed to: reduce mowed lawn by 50%, increase tree cover by 100%, increase plant diversity by 100% and retain runoff from impervious surfaces with a capacity to filter 90% of the rain events predicted in Delaware. Homeowners who participate will commit to having their landscapes altered and maintained in this manner for three years. Plantings will be installed to supplement the existing suburban landscapes as appropriate for each site. Our team will provide weekly maintenance of the landscapes. These sites will be photographed for use in the video, website and other publications.
Evaluation: The success of these demonstration sites will be evaluated by interviews conducted with the homeowners, responses from tour participants, and surveys of other homeowners in the development
Site Visitation: WMGL project sites and Applecross demonstration sites will be visited in a variety of ways.
1. Routine visitation at WMGL: When WMGL first released many acres of regularly mowed turf to meadow, they received complaints from visitors and staff. By adding “cues of care” such as mowed pathways and edges, they have reduced the concerns because the areas look purposeful (Hands and Brown, 2002; Nassauer, 1995). A demonstration site will be developed at WMGL that supplements mowing “cues of care” with desirable native plantings. This site will be interpreted for regular visitors.
2. Special events at WMGL: In 2010, 24,000 people attended events/ programs at WMGL. WMGL’s existing continuing education program will be enhanced with outreach about sustainable landscaping for improvement of water quality. A regular feature “Wednesdays at WMGL” offers workshops and tours every Wednesday at 11:30 AM. Data from our study of water quality and ecosystem services and an explanation of study sites will be included in this programming. A tour for landscape professionals of project sites will be conducted in year three of the project. The tour will be co-sponsored by the UD, The Delaware Nursery and Landscape Association (DNLA) and WMGL.
3. Applecross and WMGL Demonstration Sites: A homeowner-oriented tour of demonstration landscapes in Applecross and project sites at WMGL will be co-sponsored by the UD, Delaware Center for Horticulture (DCH) and WMGL. The tour will be publicized through the DCH’s membership newsletter. Members look forward to themed garden tours each year to learn more about gardens and garden design. This provides an excellent opportunity to expose interested homeowners to non-traditional landscape management practices.
4. Industry meetings: DNLA and Delaware Cooperative Extension (DCE) cosponsor three major professional development meetings each year. Results and images from this project will be presented at the Delaware Horticulture Industry Expo held in January or the Delaware Ornamentals and Turf Workshop held in November. A third meeting is held outdoors in the summer to demonstrate innovative industry practices and often includes afternoon tours. Demonstration sites at WMGL and Applecross will be included as tour destinations in the 2014 Delaware Summer Landscape Expo.
5. Homeowner short courses: The Delaware Master Gardener Program sponsors a series of homeowner workshops every year. Images from the demonstration sites will be used to develop a presentation as part of the Landscape Design Short Course offered by Master Gardeners.
6. Publications: An ecosystem services brochure will be published that outlines the landscape practices that yield beneficial ecosystem services. This brochure will be available online as a downloadable PDF. Information on this project will be included in the UDBG’s Sustainable Landscape webpage. Articles on this project will be written for landscape industry newsletters such as American Nurserymen. Research will be published in appropriate referred journals.
Evaluation: Follow-up surveys for DCE events are conducted with participants to document intended behavior change based on training received. We will also track website visitation and brochure requests. Surveys will be conducted after all major tours, workshops and short courses. An intervention survey of WMGL visitors will be conducted on several days in the third year of the project.
Potential pitfalls and limitations of study
This is a low risk study that will fill gaps in our knowledge of how urban vegetation abundance and diversity contributes to improved water quality, sustainable water management, and the production of important ecosystem services. All of our methods are standard and not controversial, and have been employed successfully in many studies. The success of our water quality monitoring protocols depends to some degree on storm events. However, the long study period (2.5 yrs) should enable us to get sufficient data on storm events. It is also possible that we will be unable to get sufficient participation from Applegate residents to create our model landscapes. We do not anticipate this because we (Dr. Bruck) already have a working relationship with Applegate homeowners. Moreover, Applegate was built and advertised as a green model from its inception suggesting that people who bought properties in this neighborhood were already sympathetic with green issues.
D) PROJECT TIMETABLE
Water quality sampling- Yrs 1, 2, & 2.5
Biodiversity measures; Vegetation-Yr 2; Breeding birds and caterpillars – Yrs 1, 2, 3;
Pest control monitoring – Yrs 1, 2, & 3.
Carbon sequestration estimates - Yr 2.
Pollinator measures – Yrs 1, 2, & 3.
Economic assessment – Yr 2.
Site preparation, particularly at Applecross demonstration properties- Yr 1
Education, Extension and Outreach - see descriptions above.
Manuscript preparation – Yr 3.