The Turfgrass Science team from the University of Minnesota gave two presentations and presented two posters at this year’s ASA-CSSA-SSSA Virtual Annual Meeting. Below is a listing of the abstracts, along with links to the poster PDF files.
A special congratulations to graduate student, Dominic Christensen, for placing 2nd in the Turf Management Oral competition!
Designing Turfgrass Mixtures for Roadsides
By Dominic Christensen, Joshua Friell, Jacob Jungers and Eric Watkins
Establishment and persistence of roadside turfgrass vegetation in cold climates is reduced by deicing salt, prolonged ice encasement, ill management, poor soil quality, and weed competition among other factors. This results in increased soil erosion, reduced water quality, and often greater visibility impairments for drivers. The objective of this experiment was to test a set of turfgrass species and mixtures across the state of Minnesota to identify principles of designing turfgrass mixtures for roadsides. Treatments included monocultures and various species combinations ranging from two-species mixtures up to mixtures with six species accompanied with four currently recommended roadside turfgrass mixtures. Seven locations were seeded in the fall of 2018 and 2019 for a total of 14 locations. Data were collected twice annually on turfgrass, bare soil, and weed coverage for the establishment year and species composition for seeded turfgrass species beginning a year after seeding. When averaging turf and weed coverage across the locations seeded in the fall of 2018, we found a significant time by number of species interaction on turfgrass coverage with the addition of each additional species showing greater turfgrass coverage after the first sampling time (p=0.043). Each additional species included in a mixture was also found to reduce the odds of weed coverage by 0.835 times while holding the time constant (p<0.0001). We suggest the inclusion of many adapted turfgrass species, as funds allow, to increase turfgrass and reduce weed coverage for roadsides and low-maintenance areas.
Comparing Methods for Mapping Zones of Turfgrass Adaptation in the Contiguous United States
By Maggie Reiter, Joshua Friell, Frank Rossi, Peter Wiringa and Eric Watkins
A wide range of turfgrass ecosystems exist in the contiguous United States, with variations primarily due to temperature and moisture ranges. Understanding local adaptation is important for selecting appropriate turfgrass species and cultivars. Several attempts have been made to delineate turfgrass zones of adaptation based on climate, and broader vegetation mapping frameworks like USDA Plant Hardiness Zones and EPA Ecoregions may have value. The objective of this investigation was to review existing and potential models for mapping zones of turfgrass adaptation, identify tradeoffs associated with different approaches, and explore applications for the information. We found mapping methods ranging in complexity from as general as three zones to as many as 967 distinct units of adaptation. One advantage of using frameworks like EPA Ecoregions includes the ability to identify non-contiguous regions with similar ecosystems. A limitation for practical applications is the lack of turfgrass-specific digital map data for analysis, which can be overcome with availability of ecoregionalizations available as geospatial datasets. We conclude that an improved way to delineate turfgrass zones of adaptation would use a combined approach, whereby ecosystem regions are adjusted based on turfgrass practitioner input and historical turfgrass research. Finally, we demonstrate that adaptation zones would be useful as an attribute of a turfgrass species or cultivar selection tool.
Can Arbuscular Mycorrhizal Fungi Inoculum Improve Conditions of Various Golf Greens?
By Florence Sessoms, Ryan Schwab and Eric Watkins
Association between Inflorescence Morphology and Seed Shattering in Perennial Ryegrass (Lolium perenne L.)
By Joan Barreto Ortiz, Eric Watkins and Nancy Jo Ehlke