(Multistate Research Coordinating Committee and Information Exchange Group)
Duration: 10/01/2019 to 09/30/2024
Statement of Issues and Justification
Presently, turfgrasses cover nearly 50 million acres in the United States, larger than any other irrigated crop (Milesi et al., 2005), with the turfgrass industry contributing an estimated annual economic impact of more than $40 billion. Turfgrasses are mostly grown in urban environments and depending on the use (lawns, sports fields, golf courses, or parks and passive right of ways), the level of management provided ranges from very low to high. Turfgrass is a resource that serves an important role, not only from an aesthetic standpoint, but also from a functional and environmental standpoint. Turfgrass provides ecosystems services in urban environments that are otherwise mostly made of hardscapes such as streets, sidewalks, parking lots, and concrete or pavement. For example, turfgrass systems have been shown to provide to carbon (C) sequestration (Qian and Follett, 2002), soil stabilization, filtering of water, reduction of runoff, and dust stabilization (Beard and Green, 1994). Turfgrass systems also provide recreational opportunities that are important for human physical and mental health (Ho et al., 2003; Ulrich and Addoms, 1981). With increasing urbanization occurring across the United States, demand for green spaces, parks, landscapes, and functional turfgrass areas, and proper design and management of these areas has also increased.
Research, Extension, and Education efforts are needed to continue to promote adoption of sustainable turfgrass production and management systems. In the Southern Region of the United States, turfgrass industry professionals and homeowners rely on university turfgrass science programs for information and recommendations regarding best adapted turfgrass species and cultivars, athletic field safety, fertility requirements and fertilizers, irrigation needs, mechanical and cultural practices, and sustainable strategies for improved turfgrass pest and stress management. Given the increasing public concern over turfgrasses perceived demand for excessive inputs such as irrigation, fertilizers, and pesticides, university turfgrass scientists and extension specialists have made significant strides in developing more sustainable and low-input turfgrass germplasm, cultural practices, and management programs in recent decades. Currently, some of the most important issues facing the turfgrass industry in the southern U.S. include:
1. Water: Given that turfgrasses are currently the largest irrigated crop in the U.S. (Milesi et al.,2005), turfgrass water use and irrigation continue to be heavily scrutinized, often cited by the public as being a wasteful or excessive use of potable water. As urban populations are increasing, turfgrass installations are also increasing, yet many municipalities are restricting or limiting outdoor water use for turfgrass and landscape areas (Ozan and Alsharif, 2013). While turfgrass water use research has been widely conducted in the more arid western U.S., research on the comparative water use requirements of warm-season turfgrass species and cultivars has been much more limited in the southeastern U.S. and is needed for use in development of irrigation permitting and water conservation programs in this region (Wherley et al., 2015). In addition, many areas of the south are using reclaimed and/or non-potable water (saline water) sources for turfgrass irrigation, which may encourage other unique problems. For example, Rapid Blight (Labyrinthula terrestris) is a disease that occurs with soils having elevated salinity naturally or from irrigating with a saline water source (Bigelow, Olsen, and Gilbertson, 2005). Although several turfgrass species and cultivars have good overall drought resistance and resiliency, much work is still needed regarding effects of reduced irrigation or no irrigation, as well as effects of different irrigation quality on current turfgrass species and the development and release of new, drought resistant cultivars that produce high quality turf with limited to no irrigation as well as on other aspects of their management such as pesticide use, fertility, etc.
2. Fertility Turfgrasses often require nutrient inputs throughout the growing season to maintain quality and health. Nitrogen (N) is required for growth and health of turfgrass systems and is generally the most limiting nutrient (Kussow et al., 2012). It is also lost with tissue removal via mowing. Thus, N is the driver of turf fertility programs and the nutrient most frequently applied to turfgrasses. Phosphorus (P) is also commonly applied to turfgrass systems, particularly those that have been newly established (Soldat et al., 2009). Both N and P have been shown to be a component of surface runoff from urban and agricultural systems (Shuman, 2004; Soldat et al., 2009; Wherley et al., 2009). Off-site movement of N and P from agricultural and turfgrass systems is a common concern due to potential for stimulating eutrophication as well as other human health issues. Research has shown that turfgrasses can be effectively used to limit and reduce nutrient runoff and leaching into the surrounding environment (Gross, Angle, and Welterlen, 1990; Wherley et al., 2009). However, turfgrass fertility must be managed to prevent fertilizer over or misapplication to ensure a healthy, dense, and vigorous turfgrass system. Proper turfgrass fertility management and application can inhibit disease, insect, and weed infestation, yet improper use or under/over application can have the opposite effect. Although much work has been completed in the area of turfgrass fertility and nutrient management, there is a need to provide research and extension projects that detail the proper use, application, and management of turfgrass fertilizers in urban and agricultural systems, especially for newly released cultivars.
3. Pest Control Turfgrasses often require pest management throughout the growing season to maintain quality and health. Weeds can alter the uniformity, usability, and safety of turfgrass systems (Busey, 2003). Turfgrass weeds cause issues on both low and high management turf areas. For example, weeds may cause safety issues on roadsides by obstructing line of sight and on sports fields by causing uneven footing, or could be a sign that soils are becoming compacted due to overuse or excessive foot traffic. It is important for SERA-025 faculty to research and provide extension information related to weed identification, weed prevention and control, and use of new technologies such as unmanned aerial vehicles or robots for weed management. Although management and control of turfgrass insect pests have been well studied over the past 30 years, there has also been an increased concern of protecting pollinators and other beneficial species in both urban and agricultural systems (Gels, Held, and Potter, 2002; Larson, Redmond, and Potter, 2013). Further research and extension work is needed to identify safe and proper use of current and newer chemistries as well as development of strategies that promote protection and proliferation of pollinators and other beneficial insect species (Shumann et al., 1998). Diseases are also a major concern in turfgrass systems. The climate of the Southern United States, especially in the more humid areas, is optimal for disease outbreaks under certain conditions. Some disease (ex. pythium blight) can kill a turfgrass system within a very short period of time (24-48 hrs). In addition to the aforementioned pest issues, new pests are frequently identified on turfgrass systems that require management (Entwistle et al., 2014). It is imperative that turfgrass scientists continue to develop strategies and practices for pest management to be extended to stakeholders and end users so that turfgrass pests can be effectively controlled while mitigating environmental impacts. In general, successful turfgrass pest management requires a multi-strategy approach. Regardless of the pest type, management can begin with the proactive approach of development and release of improved or resistant cultivars. Next, identifying general management strategies that promote healthy soils and healthy turfgrass systems and surrounds can help prevent pest invasions. Growing a dense turfgrass system can help reduce light to germinating weed seeds, weakening them and reducing the chance of survival. Thus, making sure conditions are optimal for turfgrass growth is important. For example, compaction, and too much and too little fertilizer and water can promote certain pests (ex. dollar weed, goose grass). Determining the proper amount of fertilizer and water, alleviating compaction issues, ensuring that turfgrass receives adequate sunlight, encouraging a diverse microbial community, and encouraging a diverse plant and insect community in the surrounds of the turfgrass system are important. When pests to become a problem, both cultural and chemical strategies may be options. Work is needed to continue to promote the safe and proper use of current and new pesticide chemistries as well as development of alternative chemical or non-chemical controls in turfgrass systems (McCarty, 2005).
The perceived use of turfgrass chemicals in the urban environment has also been under growing public scrutiny. Turfgrass managers should ensure that proper disease management and control options are being followed while minimizing the potential negative impact on the environment. Work needs to be conducted in identifying how to ensure pesticides are most effective when applied. This will minimize the need for reapplication and or higher rates and subsequently will reduce any potential hazards to the surrounding environment. For example, certain water quality characteristics can reduce the efficacy of certain pesticides.
In addition, overuse or misapplication of turfgrass pesticides can lead to pesticide chemistry resistance in weed, disease, and insect populations. Turfgrass managers unaware of pesticide resistance issues may unintentionally over applying pesticides that may potentially end up in the surrounding environment. Efforts to identify potential of pests to build resistances and educating stakeholders to these issues and management strategies is needed.
4. Shade Turfgrasses grown in the urban environment are typically exposed to shade, either from woody vegetation such as trees and shrubs, or from structures such as buildings or homes. It has been estimated that at least 25% of all turfgrass areas are maintained in some degree of shade (Beard, 1973). All turfgrasses require adequate light to efficiently perform photosynthesis. In addition, many athletic playing fields are built in stadiums or are surrounded by seating or other structures, causing excessive shade conditions. If turfgrasses do not receive adequate light quantity or quality, they will decline and possibly die out completely. It is imperative that turfgrass scientists continue to develop management practices for growing turfgrasses in the shade. This includes development of cultural strategies that are unique for plants growing in shaded conditions as well as development and release of turfgrass cultivars that are better adapted to shade. While cool-season grasses are generally more shade tolerant than warm-season grasses, cool-season species are not well adapted to grow in the Southern United States due to high temperatures, humidity, and low precipitation. Additionally, only a limited amount of work has been conducted in the area of warm-season turfgrass shade tolerance (Bunnell et al., 2005; Zhang et al., 2017). Among the warm-season grass species, there are differences in performance under shade, but work must be completed to determine the relative shade tolerance of current and new warm-season turfgrass cultivars that are overall better adapted to the South, but not necessarily best adapted to shade. Working with turfgrass breeders, efforts should be made to improve warm-season turfgrass shade tolerance.
5. Urban Turfgrass Removal and Replacement Many municipalities of the United States have enacted programs incentivizing removal or reduction in the total area of planted turfgrass (Heavenrich and Hall, 2016). This is due largely to public perception that lawns or turf may be mismanaged, overwatered, and have overuse of pesticides. However, this discounts the many environmental benefits of turfgrass and ecosystems services it provides to urban communities. Research and extension efforts are needed to more closely examine the ecosystem services and environmental impacts of turfgrass areas versus alternative landscapes developed following turfgrass removal. While citizens may have short term financial incentive to remove turfgrass from their yards, it may not be beneficial to the environment, especially if the area is still irrigated. In fact, turfgrasses have been shown to be excellent buffers and natural filters to reduce or slow down urban runoff. It is imperative that turfgrass scientists and extension specialists develop research projects and programming to examine the short and long term effects of urban turfgrass removal and replacement programs on the urban environment with an emphasis on urban heat island effects, nutrient and pesticide runoff, storm water handling and quality, soil health, and reduced functional turfgrass spaces.
Many of the issues described to this point can be addressed largely through proper turfgrass species and cultivar selection. Turfgrass breeders have worked diligently over the past 50 years to develop and release turfgrass cultivars offering improvements in turf quality, temperature tolerance, drought resistance, disease and insect pest resistance, traffic tolerance and ability to outcompete weeds (Busey, 1989). In order for a new turfgrass cultivar to be successfully adopted by producers, it must not only have improved traits, but also must make a good crop, either via seed or sod production. Turfgrass breeders must continue to use both traditional and molecular breeding techniques to continue to improve turfgrass quality and biotic and abiotic stress resistance. In addition, experimental selections must be tested over a wide variety of sites and climate conditions. The Southern Region multistate turfgrass group can serve as an excellent network to test and select these grasses over a wide range of conditions.
In fact, multistate information exchange and research projects are critical to the success of turfgrass research and extension programs in the Southern United States. Due to the existence of the SAAESD turf multistate research coordinating committee and information exchange group, our meetings and activities have proven extremely successful. For example, discussions at past SERA-025 Turf meetings have resulted in several collaborations resulting in successful federal, private, and state grants. In 2010, university breeding programs in the region (FL, GA, NC, OK and TX) received USDA Specialty Crop Research Initiative (SCRI) funding in support of a five-year project to develop warm-season turfgrasses with greater drought and salinity tolerance (Chandra, A., G. Miller, L. Nelson, K. Kenworthy, B. Schwartz, P. Raymer, S. Milla-Lewis, Y. Wu, J. McAfee, B. Wherley, B. Unruh, J. Moss, D. Martin, C. Waltz, R. Carrow, M. Palma, T. Boyer and C. Chung) for a 5-year project titled: “Genetics and Genomics to Improve Drought and Salinity Tolerance for Sustainable Turfgrass Production in the Southern United States”, which was funded by the USDA-NIFA- Specialty Crop Research Initiative for $3,802,678. More recently in 2016, university breeding and physiology programs in the region (FL, GA, NC, OK, and TX) received USDA Specialty Crop Research Initiative (SCRI) funding in support of a four-year project to evaluate warm-season turfgrass germplasm performance under limited irrigation and long-term drought (K. Kenworthy, B. Unruh, J. Erickson, M. Dukes, J. Kruse, P. Munoz, J. Zhang, P. Raymer, B. Schwartz, C. Waltz, K. Devos, A. Chandra, M. Elmore, B. Wherley, Q. Yu, T. Boyer, S. Lewis, Y. Wu, J. Moss, D. Martin, C. Chung, S. Taghvaein, G. Miller, and S. Lewis) titled “Persistence, Survival, and Recovery of Warm-Season Turfgrass Selections for Sustainable Urban Landscapes Under Limited Irrigation and Long-Term Drought”, which was also funded by USDA-NIFA Specialty Crop Research Initiative at $4,438,003. In addition to these two projects, there have been two additional projects submitted for the most recent USDA-NIFA SCRI involving SERA-025 collaboration. One is a warm-season turfgrass shade physiology and breeding project (PI Charles Fontanier) involving Oklahoma State University, Texas A&M University, Kansas State University, University of Arkansas, and University of Kentucky. The other is a warm-season turf drought and water use physiology and breeding project (PI’s Milla-Lewis and Jesperson) involving N.C. State, University of Georgia, Texas A&M University, University of Florida, Oklahoma State University, and University of California.
Research is being conducted and extension resources are being developed to provide stakeholders with pertinent research-based information regarding the performance of several new or existing turf care products and technologies. These research, extension and teaching efforts align with the goals from SAAESD’s Southern Region Priority Areas for Multistate Research Activities. More specifically, efforts address Goals 1.1, 1.2, 1.4-1.6, 4.1, 4.2, 4.4-4.6, and 5.1, 5.3, and 5.6. Best Management Practices (BMPs) are being developed to ensure acceptable levels of turfgrass quality and function while protecting and or enhancing natural resources and increasing stakeholder livelihood and quality of life for the general public. Undergraduate and graduate students enrolled in the region’s Turfgrass Science programs are learning about or directly contributing to novel research and translating research results to stakeholders for implementation. These programs are also adapting to today’s students’ desires and needs, with courses and teaching methods now integrating high impact learning experiences like hands-on, critical thinking, case-studies, and communication exercises.
As a group and/or members, develop research and extension programs that provide community leadership addressing current, emerging, and anticipated needs related to turfgrass science and its associated industries, with a focus on water conservation, nutrient management, pest management, abiotic stress management, turfgrass breeding, turf alternatives, and societal concerns (e.g., glyphosate, water quality).
Provide practical and efficient mechanisms via field days, extension publications, and training events to facilitate turfgrass industry stakeholder interactions and for stakeholders to implement research-based solutions to current, emerging, and anticipated needs.
Encourage and foster the timely exchange of information among Southern Region University Turfgrass Programs to identify current, emerging, and anticipated needs in university research, teaching, and extension programs, and discuss opportunities and strategies to strengthen these programs throughout the Southern Region.
Form collaborative, multi-state research / extension teams to develop and submit one or more federal grant proposals (to USDA and/or other major funding agencies) and obtain funding for the development of more environmentally and economically sustainable turfgrass management programs and encourage member and non-member collaboration.
Procedures and Activities
Objectives will be accomplished by meeting three of every four years, typically at or nearby to one of the institutions with a turf program in the Region. There are no annual meetings every fourth year, when faculty attend the meeting of the International Turfgrass Society. Participants exchange information regarding selected and timely research, extension, and academic topics. In addition to touring the host institution facility and/or active research sites, scientists critically review, summarize, and often lead discussions on topics of interest to the group during the two-day meeting.
Research, teaching, and extension activities in the Region often involve the common issue of turfgrass sustainability. As such, discussion topics often center on how to manage turfgrasses using cultural, chemical and biological inputs judiciously while making efficient use of non-renewable natural resources, as well as improving quality of life and preservation of environmental quality.
Anticipated procedures and activities of SERA025 members in each focus area for the proposed project period include:
1. Water Conservation/ Drought/ Turfgrass Water Use.
a) Provide the turfgrass irrigation industry with weather and/or soil moisture-based irrigation information for cool- and warm-season turfgrass systems. Turf irrigation can be scheduled using real time or historical reference evapotranspiration (ETo) data derived from species-specific crop coefficient (Kc) adjustment factors, and/or through use of soil moisture based approaches. Validating these approaches and evaluating feasibility of new irrigation technologies will reduce the amount of water used on turfgrass systems in the region.
b) Select and breed warm- and cool-season varieties for drought avoidance based on their chronic drought response and subsequent recovery from drought. Such experiments are underway at multiple locations within the Region via funding from the USDA SCRI initiative and the United States Golf Association (USGA) Green Section.
c) Develop improved water conservation practices by 1) Measuring plant responses to mowing height, fertility, applied PGRs, and suitable soil amendments; 2) Educating clientele and promoting the use of near- real-time ET for irrigation scheduling, use of plant and soil amendments that increase water use and availability, and the use of sensory, soil moisture based irrigation components designed to interact with standard irrigation system control devices (satellites and or PC based controllers); 3) identifying different irrigation water quality and influence on irrigation needs, 4) evaluating turf root zone construction and management practices that reduce offsite losses due to leaching and/or runoff of irrigation water, and 4) The release and use of low-maintenance turfgrasses which require significantly less water and are capable of tolerating poor quality irrigation water.
2. Turfgrass Fertility, Disease, Insect, and Weed Management
a) Monitoring nutrient runoff and leaching from turfgrass areas to determine the proper fertilizer application rates and schedules while minimizing detrimental environmental effects, especially pollution of ground- and surface-water supplies. Identify cultural, chemical, and biological mechanisms related to increased nutrient use efficiency and reduced nutrient leaching.
b) Documenting, publishing and investigating herbicide resistance occurrence, mechanisms and distribution, while testing and developing new herbicide chemistries.
c) Conducting basic and applied research regarding insect pest and pathogen biology and ecology leading to more effective cultural and biological control strategies, and a wiser, more targeted use of chemical pesticides.
d) Investigate and increase stakeholder knowledge of influence of environmental factors on pesticide efficacy.
3. Development of Improved Turfgrass Varieties for the Southern Region.
a) University turfgrass breeders in the Region continue to develop turfgrass varieties with improved pest resistance, lower water and nutrient requirements, and improved heat, cold, salt and/or shade tolerance. Examples of recent warm-season varietal releases include Latitude 36, NorthBridge, TifGrand and TifTuf bermudagrasses, and Pristine and Ultimate zoysiagrasses.
b) Researchers at many Universities within the Region receive funding from the National Turfgrass Evaluation Program (NTEP) which is designed to develop and coordinate uniform evaluation trials of turfgrass varieties and promising selections in the U.S. and Canada. Each NTEP Test is usually conducted for five years, and results are published online every year. Examples include the
c) Research results reported during each annual SERA025 meeting assist in the recognition and promotion of the best-performing varieties throughout the Region. The Executive Director of NTEP receives an invitation to attend each annual SERA025 meeting and to present a review/preview of this national program.
4. Developing and Conducting Educational, Extension and Outreach Programs Summarizing Research Results and Promoting Technology Transfer of the Previous 1- 4 Focus Areas.
a) Evaluating and identifying current and emerging extension and outreach avenues to effectively disseminate information to stakeholders.
b) Encouraging information exchange on student trends, program promotion, and curriculum development.
Expected Outcomes and Impacts
- Creation of multi-state, cooperative efforts in developing grant proposals, publications, and educational programs relating to sustainable turfgrass management for the betterment of industry stakeholders and citizens of the southeastern U.S
- Strengthened collaborative efforts aimed at determining the impacts of turf management practices on the environment and facilitation of more widespread adoption/implementation of best management practices across the industry.
- Cooperative development of new germplasm by university breeders through support of USDA- SCRI and other awards
- Reduction in the overall reliance by the Turfgrass Industry on water resources, and the improved water use efficiency of turfgrasses.
- Sustainability projects should result in the application of fewer fertilizers and amendments to turfgrasses, reducing the potential for nutrient runoff into local surface waters and leaching through the turfgrass root zone into ground water
- Development of best management practices will serve as science-based resources for turfgrass industry professionals, and will help guide legislators and state regulators when formulating laws and regulations governing turf irrigation and fertilization
- Collaborative turfgrass disease, insect, and weed management projects will address specific, existing, and emerging regional problems, such as: 1) Avoiding pesticide resistance in weed, insect, and fungal populations; 2) Development of alternatives to methyl bromide, MSMA, and triazines; 3) Control/management of both existing and new turfgrass pests; and 4) Development of cultural practices that promote ecosystem health and reduce reliance on pesticides
Projected ParticipationView Appendix E: Participation
Research results will be published in appropriate journals, trade magazines and electronically to continue to inform and educate interested peers, clientele and other stakeholders. In addition to the classroom, information will also be presented during national and regional professional meetings, outreach/extension programs, and industry association conferences.
In addition to our Administrative Advisors, leadership is provided by the President, Vice-president and Secretary Treasurer, who are elected for a one-year term (except during the two-year period when the meeting is not held). One representative from each University presents a state update report during the Business Meeting. Additionally, committee chairs provide a summary of committee issues and activities. One designee from each University faculty has voting privilege.
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