Several species of turfgrass have been successfully used to create high quality roadside vegetation. However, roadsides present significant challenges to growing turfgrass due to stressful conditions that can be unique in both form and magnitude. These stresses include drought, salt exposure, heat, and disease, among others. As such, a mix that is capable of taking advantage of the unique tolerances of each species is likely to produce the best chance for survival. Recent research conducted by the University of Minnesota, in conjunction with the Local Roads Research Board and MnDOT, has identified cultivars that represent the greatest level of roadside salt tolerance within each of nine cool-season turfgrass species. Using the best-performing cultivars from each of these species, 51 mixtures have been created and planted in three locations on roadsides throughout the Twin Cities metropolitan area.
Mixtures were chosen such that the contribution of each species to the overall performance of the mixture could be evaluated. Those mixtures were planted in a Randomized Complete Block design, replicated three times, and established in fall 2011. Because of the remote nature of the locations, no irrigation was possible, and no fertility treatments were applied after establishment. Beginning in fall 2011, data is being collected for two years on the plots including visual assessments of turf cover, weed encroachment, seed head production, disease, and overall quality. In addition, digital image analysis will be used to quantitatively evaluate the turf cover along the edge of the road. These data will be analyzed to identify an optimal mix of species which provides the best possible turf performance across a wide range of conditions.
Table 1. Cool season cultivars and species in mixture drought trials
Species |
Cultivar |
---|---|
creeping bentgrass |
Mariner |
Kentucky bluegrass |
Moonlight SLT |
alkaligrass |
Salty |
strong creeping red fescue |
Navigator |
slender creeping red fescue |
Shoreline |
hard fescue |
Beacon |
sheep fescue |
Marco Polo |
tall fescue |
Grande II |
Chewings fescue |
Radar |
Additional Links:
Salt Tolerance of 75 Cool-Season Turfgrasses for Roadsides: http://www.tandfonline.com/doi/full/10.1080/09064710.2012.678381
Phase I Survival Tables (.pdf)