Zoysiagrass is one of the most resource-efficient warm-season grasses because it requires less inputs. Increasing the production acreage and use of zoysiagrass will provide an economically and environmentally sustainable option for turfgrass producers (sod farms) and users (further defined under objective 3). However, sod farms have clearly identified a slower rate of establishment of zoysiagrass as a critical issue limiting production acreage and revenue generated from zoysiagrass sod production (Fig. 3). Furthermore, establishment rate on sod farms can potentially be hindered when controlling weeds by the use of some common herbicides that may cause injury or root inhibition or delay spring green-up from winter dormancy.

Turfgrass breeding programs have been working on developing new and improved cultivars of zoysiagrasses with a faster rate of establishment, wider range of adaptation (extreme temperature tolerance), and improved biotic and abiotic stress tolerance. Funding from the United States Golf Association (USGA) to a collaborative team of PD Chandra (Texas A&M), Co-PD Fry (KSU) and Patton (Purdue) over past 10 years has resulted in the development and identification of DALZ 1701, DALZ 1702 and DALZ 1808 with extreme temperature tolerance, improved drought resistance, and disease tolerance. Breeding programs at Texas A&M, NCSU, UFL, and UGA have also been working on developing new and improved zoysiagrass lines. However, information is currently lacking regarding their production cycle, re-growth after sod harvest, thatch production and its effect on sod harvestability and weed control measures during sod production. These project objectives are designed to provide answers to these questions prior to the commercial release of any of these lines. Knowledge gained from this research will enable the future producers of these new cultivars, regardless of their developer, to be better equipped to optimize and increase zoysiagrass production resulting in additional revenue for the farmer and increased performance and sustainability for the consumer.

Distinct outcomes: Objective 1

• Increase the production acreage of zoysiagrass as a sustainable and resource-efficient option for the transition zone.
• Increase farm revenue from shorter production cycles and faster growth/re-growth of recently released and soon-to-be-released, value-added, low-input cultivars.
• New knowledge on herbicide options to use during sod production of newly released and soon-to-be-released cultivars.
• Publication of an up-to-date peer-reviewed article as a benchmark of the current knowledge on zoysiagrass sod production.

Objective two addresses difficulties that have been noted with the performance of dense, fine-textured zoysiagrass cultivars, including Innovation and new genotypes, after sod is harvested at the FARM and laid on the LAWN. Thatch accumulation during production can occur and is often impacted by mowing height and nitrogen fertilization. Higher mowing heights and nitrogen levels during production encourage higher thatch production (Gaussoin et al., 2013). As detailed in the narrative, zoysiagrass roots can grow in thatch and may not penetrate soil effectively when sod is laid; as such, effective thatch management is critical. Issues with thatch in sod can impact aesthetics by minimizing rooting, causing greater levels of winterkill, and reducing drought resistance. A reduction in turf performance impacts turf producers and managers negatively and reduces the positive impacts of turf to the ecosystem. New zoysiagrass genotypes may respond differently to production management practices at the FARM and cultural practices after sod is laid. Specifically, mowing height on the LAWN site can impact quality and performance of new zoysiagrass genotypes. Experiments below will focus on the impact of mowing at standard lawn height and mowing at heights used on golf course fairways. Soil types at the FARM and LAWN will also be evaluated, as differences between the two can also impact root development after sod is laid.

Distinct outcomes: Objective 2

• New knowledge on managing standard zoysiagrass cultivars in comparison to new genotypes for rate of growth and thatch accumulation to help guide selection of new cultivars.
• Guidance to growers (FARM) on best management practices for production, with focus on mowing heights and nitrogen rates and their impact on thatch accumulation.
• Guidance to end-users (LAWNS) on impact of mowing height and soil type (at grower vs. end-user) on growth and quality of recently laid sod.
• Recommendations on cultural strategies for optimizing transplant success.

A main barrier to adopting low-input species is the lack of data on turf management post-transplant. Preliminary data from a needs assessment of residential, commercial, and athletic facilities users (LAWN) of zoysiagrass showed that their top two issues when managing their turf are slow recovery, and initial establishment. The same survey illustrated that end-users prioritize investing research dollars on faster establishment, tolerance to environmental stress and thatch management of zoysiagrass. The trends above demonstrate the need for research-based information that can assist the successful transplant and establishment of zoysiagrass in LAWNS. Yet, it is unknown the current cultural practices of commercial, residential, and athletic facilities regarding thatch management, mowing height, agrochemical use, and planting sites characteristics in LAWNS. It is also unknown the preferences of end-users towards zoysiagrass attributes, as well the most salient issues when managing turfgrasses in the Southern U.S.

Distinct outcomes: Objective 3

• Assess mowing requirements for a warm-season lawn.
• Quantify the required maintenance inputs (mowing, fertilizer, pesticides) for a quality low-input warm-season lawn.
• Assess consumer demand, preferences, and willingness to pay for low-input zoysiagrass cultivars.
• Investigate sod buyers’ preferences and rationale regarding warm-season low-input zoysiagrass cultivars.

There is a need to bridge the knowledge gap from research for best management practices of zoysiagrass for FARM (producers) to LAWN (end-users) through outreach education. Utilizing knowledge gained in the project through objectives 1, 2, and 3, we will create targeted extension outreach efforts. Objective four includes producing extension outreach products and programs to promote best management practices for producers and consumers of zoysiagrass; disseminating information through outreach education opportunities at the national, regional, and local levels; 

Distinct outcomes: Objective 4

• Knowledge gained on producing and managing new zoysiagrasses able to improve sustainability.
• Adoption of best management practices for production and transplant success of zoysiagrass.
• Increased consumer awareness of new low-input technology (cultivars).
• Development of novel extension publications to aid sod producers and consumers.