Manure and wastewater disposal on land holdings of large dairies have contributed to phosphorus accumulation on watersheds in the Southern U.S. A learning organization comprising dairy, turfgrass, and compost producers and university research and extension faculty was assembled. This organization or ‘learning system’ focused on concerns about phosphorus loads on watersheds and the sustainability of both dairy and turf industries in the Southern Region. The human activities of participants in the learning system during this one-year project, including four project meetings and a one-day workshop, were relevant to three project objectives: 1.) Organize the learning system, 2.) Characterize turfgrass responses and the fate of nitrogen and phosphorus after surface applications of manure, and 3.) Evaluate the operational and economical feasibility of exporting manure sources of nutrients from farms and watersheds through sod.
During project meetings, participants identified information and analyses that were needed to develop and evaluate a system for exporting manure sources of phosphorus through sod. Information about responses of turfgrass establishment, production, and quality after manure application was developed in replicated plots. The production and quality of ‘Tifway’ bermudagrass and ‘Prairie’ buffalograss during the 15 months from planting to the first sod harvest was equal or better for manure compared to fertilizer sources of nutrients. Sod harvests of bermudagrass and buffalograss during summer, 1999 removed 45 to 62% of phosphorus applied as manure before and 1 year after planting. The first sod harvest indicated surface accumulations of manure phosphorus were effectively removed and exported through turfgrass sod. Manure influences on turfgrass regrowth after sod harvest and on recovery of the manure-grown sod after transplanting remain to be evaluated.
The fate of nitrogen and phosphorus after surface applications of manure and fertilizer were evaluated on common bermudagrass plots. The volume and nutrient concentration in runoff from the 8%-slope of plots was monitored after four natural rainfall events during each of two monitoring periods. Metal barriers were inserted into soil around plot perimeters and metal chutes on the down-slope end of plots channeled runoff into reservoirs. Nitrogen and phosphorus losses in runoff were compared between manure and fertilizer sources of nutrients. During a relatively large runoff event that occurred 3 days after equal phosphorus rates were applied as manure or fertilizer on the bermudagrass, the concentration of phosphorus in runoff from fertilized plots was 5.5 times greater than manured plots. Dissolved phosphorus concentrations in plot runoff were comparable between manure and fertilizer sources of equal phosphorus durng the second, third, and fourth rainfall events. Manure sources of nutrients appeared to be less soluble and less vulnerable to loss in surface runoff than fertilizer sources soon after nutrients were applied to the bermudagrass sod. Potential losses of manure and fertilizer sources of nitrogen and phosphorus from the bare soil remaining after sod harvest and from transplanted sod remain to be quantified.
Information from plot-scale studies, demonstrations on dairy fields, and project participants will be used to develop recommendations for an integrated dairy and sod production system and to identify questions and knowledge gaps for future research and development efforts. In addition, project participants will use information from this and emerging projects to evaluate the operational and economic feasibility of exporting manure sources of nutrients through turfgrass sod. The export of manure sources of nutrients through sod is expected to contribute to the economic and environmental sustainability of both livestock and turfgrass industries.
1. Involve dairy and sod producers, professionals from industry, and public agencies in a learning system for developing and evaluating sod-production enterprises that redistribute and add value to phosphorus and nitrogen in dairy manure and wastewater.
2. Plan research that evaluates the operational and economical feasibility of exporting phosphorus and nitrogen from dairies in turfgrass sod and in manure used for sod production.
3. Develop baseline data about sod establishment, productivity, and quality and the fate of phosphorus and nitrogen after surface applications of manure and/or wastewater.
4. Develop a regional project and proposals for submission to the Texas Advanced Technology Program, NRICG Program, SARE, and the turfgrass industry for development of a system for turfgrass sod production in association with animal agriculture.
Both dairy and turfgrass production have been growth industries in Texas and adjoining states during the past 20 years. In Texas, producers’ annual income from milk sales now exceeds $800 million and from turfgrass sod more than $60 million. The two industries do have infrastructure characteristics in common. First, dairies require large nutrient inputs, largely as purchased feed for milk cows. Sod production requires large inputs of nutrients, but as fertilizer. Second, production operations for both industries locate within a “hauling distance” of large urban centers in order to access markets for perishable products and input suppliers. Third, a large proportion of both sod and dairy producers own and exercise autonomy over the land and capital assets required for production. As a result, their motivation for good stewardship of natural resources and of environmental quality is strong (Ervin and Smith, 1994). Finally, economies of scale have contributed to increases in the size of both dairy and sod farms as both industries have grown.
The growth in size of farms has created one difference between the dairy and turfgrass-sod production that presents an unrealized opportunity for improving the sustainability of both industries. Of the nutrients imported and consumed as feed, dairies export less than one third of the nitrogen and phosphorus in milk and animal products. In contrast, all of the nitrogen and phosphorus localized in the leaves, roots, and the soil layer that comprise sod are exported in the harvested product. The opportunity for improving sustainability is through use of the excess of nitrogen and phosphorus on dairies, primarily as composted manure, as inputs for sod production.
The excess of nutrients on dairies resulted from confinement of large animal numbers in open lots and enclosed facilities. The excess became problematic as manure and wastewater were disposed on adjacent fields at rates based on N requirements of crops and pasture. Phosphorus accumulated because the ratio of phosphorus to nitrogen in dairy manure was two times the relative amounts used by perennial and annual crops (Sharpley, et al., 1994). A recent sampling of the upper 2 cm of soil on dairy fields in a central Texas watershed revealed soil test phosphorus concentrations greater than 200 mg kg-1 in 46% of the samples (Feagley, unpublished data).
Although owners of most dairies complied with state and federal regulations and adopted one or more best management practices (Sweeten, 1994), elevated phosphorus concentrations were reported in several reservoir and stream sites on one Texas watershed (McFarland and Hauck, 1999). The phosphorus and nitrogen concentrations in storm water runoff from the watershed were positively correlated with the percentage of land area occupied by dairy waste-application fields. The release of the surface excesses of phosphorus in runoff from dairies is of concern because phosphorus can contribute to eutrophication and limit potential human use of surface waters (Sharpley et al., 1994).
Landowner options for more efficient use of manure phosphorus include manure analysis, application rates that match crop requirements and prevent loss in runoff, and programs encouraging manure movement and distribution on larger land areas (Sharpley et al., 1994). It seems a simple matter to reduce rates of phosphorus application as manure and wastewater, but there are economic implications when constraints are imposed on rates of waste disposal on fields adjacent to animal production. In many areas dominated by animal agriculture, there simply is no economically viable alternative to land application (Daniel et al., 1998). The cost of transporting manure more than short distances from the site of its production often exceeds its nutrient value. As a result, large-scale transportation of manure from livestock operations to nutrient-deficient areas for crop production is generally not occurring. For example, 7.3% of the 92,100 ha in one drainage basin of the Upper North Bosque watershed in central Texas was used for waste-application fields in 1995 (McFarland and Hauck, 1997). The manure of 34,000 milk cows and 700 calves, containing 680,000 kg of phosphorus, was applied to 6700 ha annually. The manure of 83,000 additional milk cows is disposed on fields of adjacent drainage basins of the same watershed.
A recent headline in the Waco Tribune Herald reflects stakeholder concerns about water quality on the watershed, “Troubled Waters: Pollution Impairs the Bosque River and Affects Waco’s Water Supply,” (Smith, 1999). Advisory committees of stakeholders have already joined with regulatory agencies to establish Total Maximum Daily Loads (TMDLs) for phosphorus and other contaminants in impaired bodies of water on Texas watersheds. After extensive debate, the advisory committee for the Upper North Bosque watershed was dissolved and the State of Texas mandated a 50% reduction in nutrient loading of impaired water bodies on the watershed.
The export of nutrient excesses as manure-grown sod to nutrient-deficient areas or as composted manure to sod farms will contribute to reduced nutrient loads and prevent release into water bodies on impaired watersheds. In addition, sod is a high-value commodity (gross annual income per hectare of bermudagrass sod = $6,500) that offers the potential for adding value to the phosphorus and nitrogen in manure. Rather than recycling nutrients within a dairy, phosphorus and nitrogen in leaves, roots, and the surface layer of organic matter and soil in sod can be exported from waste-application fields, farms, and watersheds on which livestock production is concentrated. Sod production and sales offer an opportunity for diversifying the cropping system on the dairy and for development of locally-owned businesses that could enter into contracts to produce and market the turfgrass sod . Livestock producers in central Texas have expressed their preference animal husbandry and the opportunity exists for outside contractors and businesses to produce turfgrass sod, manage manure and wastewater disposal on land, and harvest and market the sod.
Animal manure and sewage sludge have long been used to amend soils for perennial grass establishment and culture (Lund et al., 1975). Annual applications of 90 Mg ha-1 of dairy manure on a forage biotype of bermudagrass produced hay yields equal to or greater than yields from fertilizer sources of nitrogen (470 kg ha-1) and phosphorus (225 kg ha –1). Turfgrass seed, sod, and sprigs have similarly been established and grown on soils amended with composted sewage sludge and other sources of organic waste (Angle, 1994). Compost rates up to 200 Mg ha-1 were incorporated into top soil or left on the soil surface for production of Kentucky bluegrass and red fescue. Seedling establishment rate and soil pH, cation exchange capacity, aggregation, organic matter, and water content were increased after compost applications (Murray, 1981). In contrast, soil bulk density and sod weight per area unit were reduced. Unfortunately, compost nutrient content and removal in sod components were not measured.
This research is the first to our knowledge that evaluates a strategy for reducing nutrient loads on watersheds through the export of manure phosphorus through sod. Rather than focusing on phosphorus export through hay or clippings alone, this research investigates the utility of removing surface applications of manure with the layer of sod. In addition to improvements in the soil layer that enhance turfgrass maintenance and regrowth after harvest, manure sources of phosphorus and other nutrients can enhance turfgrass recovery and quality when harvested sod is transplanted. The use of composted sewage sludge has increased the aesthetic quality of turfgrass compared to a treatment fertilized with ammonium nitrate (Angle, 1994). Compost amendments helped maintain “greenness” of sod during summer drought and the addition of compost during sod production enhanced the overall quality of turfgrass for 510 days after sod was harvested and reestablished. In addition, the slow release of nutrients from raw and composted sewage sludge avoided the surge of growth and associated mowing costs inherent to fertilizer applications (Angle, 1994).
The clustering of dairies on watersheds in central Texas provides a timely opportunity for developing and evaluating the feasibility and sustainability of system for conserving, exporting, and adding value to manure sources of phosphorus and nitrogen through turfgrass sod. Yet, the development and evaluation of the system is not an objective problem, simple or complex, that can be solved by outside experts through technological solutions. Rather, involvement of local stakeholders in the complex issues concerning livestock and sod productivity, environmental quality, and human well-being is needed (Bawden, 1995). The involvement of dairy and sod producers in this project, in addition to faculty from research and extension agencies, fostered cooperation between two growth industries in which owner-operated family farms predominated. The challenge was to achieve a people-centered initiative that linked system development to the social, economic, and environmental context of the dairy and turfgrass sod industries (Macadam et al., 1995). In addition to research about turfgrass responses to dairy manure, this project used producer inputs for planning and conducting future research about turfgrass production and economics on farms. Dairy and sod producers contributed to development of information and an infrastructure for processing, marketing, and redistributing manure sources of phosphorus and nitrogen to nutrient-deficient areas (Sharpley et al., 1994).
The focus of inquiry was expanded from farms as systems that interact with surrounding environments to farms as learning systems that coevolve with biophysical and social environments (Bawden and Packham, 1993). Systemic learning was expected to emerge from conversations about what was initially perceived as problematic and about new issues that emerged during inquiry (Bawden, 1995). The research and extension faculty who participated in this approach were as concerned with helping participants develop new, systemic ways of learning and taking action as with development of the sod production system.
Development of learning system. A Soft Systems Methodology (SSM) was used as a model for structuring activities of stakeholders in the planning project (Checkland and Scholes, 1990, Macadam et al., 1995, Mills-Packo et al., 1991, Vietor and Cralle, 1992, Vietor et al., 1992, Wilson and Morren, 1990). The activities included evaluation of what was problemmatic and development, application, and evaluation of ideas alleviating the excess nutrient loads on the Upper North Bosque watershed. In addition, the experience gained through meetings and collaborations among stakeholders contributed to development and improvement of the ways we worked together. The SSM provided a model of systems practice in which collaborators learned about situations shared, including the learning system itself.
Stakeholders and meetings. The stakeholders in this planning project were organized to represent different worldviews of what was problematic and to foster contacts with additional stakeholders during the course of the project. . An organizational meeting was held at Texas A&M University on June 23, 1999. The project team met in quarterly meetings on September 28, 1999 and January 10, June 6, and September 20, 2000. A one-day workshop was offered by project participants at the Texas A&M University Research and Extension Center in Stephenville, Texas on June 6. County extension agents, research scientists, and representatives of turf, composting, and dairy industries were invited to learn about the project activities, tour plots, and offer feedback about our progress and the feasibility of the sod production system. The final project meeting was held in conjunction with the Texas A&M University Turfgrass Field Day. Critical conversations among participants in meetings were used to identify and design purposes and activities for proactively addressing our mutual concerns and for improving situations in both dairy and turf industries. In addition, participants contributed to development and revision of project objectives and methods in proposals for continued funding of the project activities.
Baseline data for sod production. Manure responses of sod production of ‘Tifway’ bermudagrass and ‘Prairie’ buffalograss were evaluated in replicated plots at the Texas A&M Turfgrass Research Facility at College Station, Texas. The same treatments were imposed on replicated plots of ‘Texas’ bluegrass at the Texas A&M Research and Extension Center in central Texas. Manure rates that delivered 100 and 200 kg phosphorus (P) ha-1 annually, with and without supplemental nitrogen (N) fertilizer (Total N rate = 280 kg ha-1 y-1), comprised four of the replicated treatments for each turfgrass species. The manure-treated plots were compared to unfertilized controls and to plots that received monthly applications of commercial fertilizer at rates that did not exceed 280 kg N and 100 kg P ha-1 y-1. Control plots received no nutrients. The first manure application preceded planting of ‘Tifway’ bermudagrass and ‘Prairie’ buffalograss during April, 1998. Drought conditions during 1998 slowed establishment of the turfgrass and manure was applied a second time at the respective annual rates in March, 1999. Sod was harvested the first time for bermudagrass during July, buffalograss during August, and bluegrass during October, 1999. Turfgrass quality was visually rated previous to the first sod harvests.
Pilot-scale evaluations of sod responses to manure were established on land provided on Mark Quinn’s feed yard and Harold Pack’s dairy. Mark Quinn of Stoney Point feed yard teamed with Sam Peterson of Gardner Turfgrass to evaluate bermudagrass and bluegrass establishment at manure rates that provided from 0 to 702 kg ha-1 P. Manure rates that delivered 200 kg ha-1 y-1 of P, with or without supplemental N, were compared to control plots of bermudagrass on the Pack dairy.
Both the plot- and pilot-scale plots were mowed at the optimum height for sod production of each species. Ratings of stand density and turfgrass quality were recorded after establishment. Clippings will be collected to quantify growth rate and nutrient use of the turfgrass. Sod will be harvested and sampled at 6- to 9-month intervals and sod strength, sod nutrient content, residual nutrients in soil, and grass recovery rates after sod harvest will be measured as the project continues.
Baseline data for nutrient losses. In addition to evaluations of sod production, replicated plots of bermudagrass were established to quantify nutrient loss in runoff on a clay-loam soil that was excavated to create an 8% slope. The major axis of plots (1.5 x 4 m) was oriented down-slope. H-flumes and subtending reservoirs were installed at the base of the slope of each plot. Both the nutrient concentration and volume of surface runoff from plots were sampled and analyzed after natural rainfall events. Manure treatments comprised annual rates of 100 and 200 kg ha of P that were split between applications at 6-month intervals after establishment of the bermudagrass. The manure treatements for each species were compared to unfertilized controls and to plots that receive commerical fertilizer at the rates described in evaluations of sod production.
Economic analyses. The costs and returns of sod production on dairies and sod farms were determined from producer estimates and related to manure treatments, production site, and the logistical requirements of sod and manure hauling and marketing. The cost of reducing probabilities of phosphorus loss through sod production are being compared to costs of alternative practices for managing manure and wastewater sources of phosphorus and nitrogen, including direct sale of composted manure and other best management practices.
The learning system of stakeholders. The learning system of dairy and turfgrass producers and research and extension faculty contributed to development and evaluation of project objectives and plot- and pilot-scale studies of turfgrass responses to manure sources of nutrients. Learner activities were similar to those in a more general model of a system for enhancing the relevance of agricultural research to stakeholder concerns (Vietor and Cralle, 1992).
Nutrient removal through sod production. Baseline data concerning manure responses of sod during establishment and production were collected on the replicated plots. Two treatments comprised annual manure applications that supplied approximately 100 and 200 kg P ha-1 y-1. Two treatments received the same P rates as manure, but with supplemental N fertilizer. The P content of clippings differed significantly (P=0.02) among the six treatments applied to Tifway bermudagrass. Turfgrass quality and nutrient content of bermudagrass clippings were directly related to the amounts of N and P applied as manure, but supplemental N fertilizer did not increase P removal in clippings compared to manure only. The manure sources of nutrients yielded quality ratings and nutrient contents of clippings comparable to or greater than fertilized plots.
The P amounts removed in clippings of Buffalograss differed significantly among treatments. The P removal in clippings of the control plot were smaller than all treatments receiving N fertilizer or a high manure rate.
The P concentrations in subsamples of sod components were analyzed to estimate the amount of P removed during the first harvest. The P amount removed in soil plus plant components of Tifway bermudagrass averaged 45% of the total P applied in two annual manure applications. The P amount removed in the plant component of sod from the control was significantly (P=0.01) smaller than the manured treatments. The P removal in the soil component of sod differed significantly between the two rates of manure P (P=0.01), but was not increased by additions of supplemental N for either rate of manure P.
The percent of total applied P removed in buffalograss sod did not differ significantly among treatments and ranged from 52 to 62%. The P amount recovered in the plant component of the buffalograss controls was significantly (P = 0.01) smaller than treatments receiving fertilizer or manure. The P amounts in the plant component of sod from the larger of two rates of manure P, with or without supplemental N fertilizer, were significantly larger than the treatment that received N fertilizer only. Similar to the plant component, P removed in the soil portion of sod differed significantly among treatments (P=0.001) and amounts in sod of the larger rate of manure P were greater than the lesser rate. The P removal in sod of the larger rate of manure P was 125 kg ha-1 larger than the smaller rate.
Clearly, sod harvest provided an effective method for removing and exporting manure sources phosphorus that were applied during turf production. Sod removed from 10 to 30-fold more P than harvests of clippings throughout the production period. Yet, increases in extractable P in soil beneath the sod layer of the larger rate of manure P indicated excess P was leached from the sod layer. The loamy-sand texture of soil in which sod was grown could have contributed to leaching of excess P and reduced potential recovery in the sod layer.
Nutrient losses in surface runoff. The fate of N and P, including potential losses, in surface applications of the manure nutrients was evaluated on an 8% slope of common bermudagrass sod. The experiment comprised 3 replications of two rates of manure phosphorus (100 and 200 kg ha-1 y-1), two rates of fertilizer phosphorus (50 and 100 kg ha-1 y-1), and a control on the bermudagrass slope. Plots were 1.5 x 4.5 m, bordered by sheet-metal barriers, and subtended by H-flumes and 310-L reservoirs. The annual P rates of each manure and fertilizer were split into two applications, which were applied at the beginning of two monitoring periods.
In 1998 and 1999, comparisons between P sources did not reveal any statistically significant differences in runoff volume. During 1998 and 1999 monitoring periods, there were significant differences (P = 0.05) among volume means of events. The first, third, and fourth rain event of 1998 and 1999 produced significantly greater volumes than the second rain event. Although the application rate of P did not significantly affect runoff volumes in 1998, runoff volumes in 1999 were significantly affected (P = 0.05). A trend towards decreasing volume as P application rate increased was observed.
Runoff concentrations of P differed significantly (P = 0.05) between the two monitoring periods and all interactions involving year were significant. Therefore, runoff nutrient concentrations were analyzed separately for each monitoring period (1998 and 1999). All nutrient losses are presented as concentrations (mg L-1).
In 1998 and 1999, dissolved P was significantly affected (P = 0.05) by event, P application rate, P source, and P source by application rate interaction. Dissolved P concentrations in surface water runoff were affected by nutrient source and runoff event during 1998 and 1999. The dissolved P concentrations of manured plots were greater than inorganic fertilizer treatments in 1998, but nutrient concentrations of the first event in 1998 were an order of magnitude below the concentrations in the first event of 1999. The dissolved P concentrations in the first runoff event of were 8 times greater than mean concentrations of 1998 for inorganic fertilizer. Events following the first runoff event in 1999 produced dissolved P concentrations comparable to all 1998 runoff events. In 1998, a 60-d period between manure application and the first runoff event decreased the potential for excessive dissolved P losses in surface water runoff for all runoff events. Dissolved P concentrations in runoff during 1999 decreased significantly (P = 0.05) after the initial runoff event. Phosphorous near and within the soil surface contributed to the concentration of dissolved P in runoff losses in 1998 and in losses during events following the initial runoff event in 1999. The relatively large dissolved P levels in the first event of 1999 were caused by the application of fertilizers before the runoff event.
During a monitoring period in Spring, 1999, dissolved P concentrations of runoff were determined for four runoff events that followed manure and fertilizer applications. During the large rainfall event just 3 days after nutrients were applied, dissolved P concentrations in runoff from plots that received 50 kg ha-1 of P fertilizer were 5.5 times greater than plots receiving 50 kg ha-1 P as manure. The bermudagrass sod minimized sediment-bound losses of P in runoff (< 1mg L-1). The slow release of manure sources of P prevented the relatively large losses observed for fertilizer sources. The slow release of P was evident in slightly larger dissolved P concentrations in runoff of manured compared to fertilized plots for events II, III, and IV.
Educational & Outreach Activities
Gaudreau. J.E. 1999. Effects of Dairy Manure and Inorganic Fertilization on Runoff Water Quality. M.S. Thesis, Texas A&M University, College Station, Texas
Griffith, E.N. 2000. Export of Manure Sources of N and P through Turfgrass Sod. M.S. Thesis, Texas A&M University, College Station, Texas
Gaudreau, J.E., R.H. White, D.M. Vietor, and G.R. Taylor. 1999. The effects of dairy manure and inorganic fertilizer on runoff water quality for common bermudagrass. P. 122, In Agronomy Abstracts. Annual meeting of Crop Science Society of America, Salt Lake City, UT.
Griffith, E.N., D.M. Vietor, R.H. White, and T.L. Provin. 1999. Export of manure source of P in turfgrass sod. P. 31, In Agronomy Abstracts. Annual meeting of American Society of Agronomy, Salt Lake City, UT.
Vietor, D.M., R.H. White, and T.L. Provin. 2000. Environmental risk of manure and fertilizer applications on turf. P. 44, In Agronomy Abstracts. Annual meeting of American Society of Agronomy, Minneapolis, MN
Najjar, N.F., F.M. rouquette, Jr., D.M. Vietor, V.A. Habey, G.W. Evers, J.P. Muir, R. Jones, and M.J. McFarland. 2000. Nonpoint source phosphorus from grazinglands. Annual Beef Field Day Report, No. 2000-1, p. 89-90, Texas A&M University Research and Extension Center, Overton, TX.
The impacts of the project are most evident in the increased number of project participants and initiatives of sod and livestock producers on the project team. Drs. Darrell Bosch and Mary Leigh Wolfe from Virginia Tech.; Dr. Allen Torbert, USDA-ARS, Temple, Texas; Dr. Sandy Stokes, Texas A&M University Research and Extension Center, Stephenville, and Dr. C.L. Munster, Agricultural Engineering, Texas A&M University have expanded the technical expertise of the project team. In addition, county-level extension agents and turf industry representatives who participated in the June-6 workshop have established working relationships with members of the project team.
In addition to information disseminated through the project workshop and field days, the demonstration plots established by Mark Quinn and Sam Peterson on land adjacent to Quinn’s feed yard have fostered connections between livestock and turf production systems. Trinity Turf Nursery has arranged to use manure from Quinn’s feed yard for sod establishment and production. In addition to the benefits of slow P release from manure during sod production and after transplanting of harvested sod, manure application can increase water holding capacity of soil and irrigation efficiency. In addition, manure additions were expected to prolong the duration of sod production under the constraints of the finite soil resources of production fields owned by Trinity Turf Nursery.
Expansion of working relationships between livestock and turf industries will contribute to future impacts of the project. For, example Mark Quinn and Sam Peterson are collaborating in an effort to produce sod on Quinn’s land holdings near the feed yard. The project will continue to provide information about turf responses to manure sources of N and P, about refinements in production systems for high-value turf species, and about upper limits on manure rates on sod fields. For example, Quinn and turf producers need information of potential nutrient losses to leaching and runoff after sod is transplanted. In addition, losses of manure nutrients applied to exposed soil after sod harvest need to be quantified.
Operational and economic feasibility.
The information from plot-scale studies and the knowledge and experience of project participants was used to evaluate the operational and economic feasibility of exporting manure sources of nutrients through turf sod. Preliminary economic analysis of enterprise budgets showed very little difference between manure and fertilizer sources of N and P in the total cost of producing sod. The on-farm costs of manure N and P were less than fertilizer, but costs of moving manure N and P to the sod production site were much greater. The manure grown sod could attract a price premium, but marketing costs are expected to be greater than traditional wholesale and retail markets for fertilizer-grown sod. Additional production data and economic analyses are needed to evaluate contributions of manure-grown sod to the economic and environmental sustainability of both livestock and turf industries.
The progress of plot-scale and on-farm experiments and demonstrations were presented at Turf field days in 1998 and 2000 and during a one-day project workshop on June 6, 2000:
Vietor, D.M., and E.N. Griffith. 1998. Sod production with recycled nutrients. Texas A&M Universtiy Turfgrass Field Day, College Station, TX, September 16.
Vietor, D.M. and J.E. Gaudreau. 1998. Fate of organic and inorganic nutrients applied to turfgrass. Texas A&M Turfgrass Field Day. College Station, TX September 16.
Vietor, D.M., R.H. White, T.L. Provin, M. Quinn, and S. Peterson. 2000. Phosphorus loss in simulated runoff from manure-grown sod. Texas A&M Turfgrass Field Day, College Station, TX, September 20.
Vietor, D.M. and R.H. White. Regional Workshop on Manure Use and Export through Sod Production. June 6, 2000. Texas A&M University Research and Extension Center, Stephenville, Texas.
Areas needing additional study
Angle, J.S. 1994. Sewage sludge compost for establishment and maintenance of turfgrass. P. 45-51, In A.R. Leslie (ed) Handbook of Integrated Pest Management for Turf and Ornamentals. Lewis Publishers, Boca Raton.
Bawden, Richard. 1995. Systemic Development: A Learning Approach to Change. Occasional Paper # 1, Center for Systemic Development, University of Western Sydney, Hawkesbury, Australia.
Bawden, R.J., and R.G. Packham. 1993. Systemic Praxis in the Education of the Agricultural Systems Practitioner. Systems Practice 6:7-19.
Checkland, P.B., and Jim Scholes. Soft Systems Methodology in Action. John Wiley & Sons, Chichester. 329 pages.
Daniel, T.C., A.N. Sharpley, and J.L. Lemunyon. 1998. Phosphorus and Eutrophication. J. Environ. Qual. 27:251-257.
Ervin, D.E., and K.R. Smith. 1994. Agricultural industrialization and environmental quality. Choices, Fourth Quarter: 7.
Lund, Z.F., B.D. Doss, and F.E. Lowry. 1975. Dairy cattle Manure- Its effect on yield and quality of coastal bermudagrass. J. Environ. Qual. 4:358-362.
Macadam, R., R. Van Asch, B. Hedley, E. Pitt, and P. Carroll. 1995. A case study in development planning using a systems learning approach: generating a master plan for the livestock sector in Nepal. Agric. systems 49: 299-323.
McFarland, A.M. and L. Hauck. 1999. Relating agricultural land uses to in-stream stormwater quality. J. Environ. Qual. 28:836-844.
McFarland, A.M. and L. Hauck. 1997. Livestock and the Environment: A National Pilot Project. Texas Institute for Applied Environmental Research PR97-02, Tarleton State University, Stephenville, TX.
Mills-Packo, P.A., K. Wilson, and P. Rotar. 1991. Highlights from the use of the soft systems methodology to improve agrotechnology transfer in Kona, Hawaii. Agric. Systems 36:409-425.
Murray, J.J. 1981. Utilization of composted sewage sludge in sod production. p. 544. In R.W. Sheard (ed) Proc. Fourth Internat. Turfgrass Research Conf., Univ. Guelph, ON.
Pote, D.H., T.C. Daniel, A.N. Sharpley, P.A. Moore, Jr., D.R. Edwards, and D.J. Nichols. 1996. Relating extractable soil phosphorus to phosphorus losses in runoff. Soil Sci. Soc. Am. J. 60:855-859.
Sharpley, A.N., S.C. Chapra, R. Wedepohl, J.T. Sims, T.C. Daniel, and K.R. Reddy. 1994. Managing agricultural phosphorus for protection of surface waters: Issues and options. J. Environ. Qual. 23:437-451.
Smith, R.L. 1999. Troubled Waters: Pollution Imparis the Bosque River and Affects Waco’s Water Supply. Waco Tribune Hearld 107(76):1.
Sweeten, J.M. 1994. Producers’ response to waste management and regulatory policy for sustainability of concentrated livestock feeding. In D.E. Storm and K.G. Casey (eds) Proceedings of the great Plains Animal Waste Conference on Confined Animal Production and Water Quality: Balancing Animal Production and the Environment. pp 192-199. Great Plains Agricultural Council Pub. No. 151.
Vietor, D.M., and H.T. Cralle. 1992. Value-laden knowledge and holistic thinking in agricultural research. Agriculture and Human Values IX(3): 44-57.
Vietor, D.M., H.T. Cralle, and J.M. Chandler. 1992. Science, technology, and systems: A hierarchy of inquiry. Weed Technology 6:452-461.
Wilson, K., and G.E.B. Morren, Jr. 1990. Systems Approaches for Improvement in Agriculture and resource Management. Macmillan Publishing Company, New York. 361 pages.