Professor of Crop and Soil Sciences at the University of Georgia College of Agricultural and Environmental Sciences, Dr. Patrick McCollough has been working to develop weed control recommendations for new turfgrass varieties, which NG Turf will bring to market this fall. In advance of these upcoming releases, we talked to Dr. McCollough about the lengthy process involved in bringing new cultivars to the market.
What goes into developing a new variety of turfgrass?
New varieties come to the industry after years of development starting with university breeding efforts.
They usually come from experimental lines that show potential in the initial screenings for turf quality, improved tolerances to stress or improved color.
Over time and through testing at multiple locations these varieties then make it to the next round of screenings that will eventually lead to a commercially developed variety that is available to the industry.
The licensing and getting cultivars registered can take years with a university. The new variety is licensed to a grower that is then able to sell that grass to the industry through a partnership with the university that helped develop that new variety. Depending on the turfgrass species, it could take up to ten years for the grass to leave the greenhouse and actually make it to a commercial release.
Dr. Patrick McCollough
Dr. Patrick McCullough serves as a turfgrass weed scientist breeder at the University of Georgia in Griffin. He conducts weed science research and extension activities related to turfgrasses and teaches the weed science component of Turfgrass Pest Management.
McCullough earned a Ph.D. in turfgrass weed science at Rutgers University. He also earned an M.S. degree from Clemson University and a B.S. degree from Western Kentucky University.
How many experimental lines are tested before a few viable candidates are identified?
Varieties can start from thousands of experimental lines that are screened out through greenhouse research.
The lines are thinned down to a number that’s workable in the field, then through years of testing, they will take the best from that research and test the quality and aesthetics of that turf line in various locations to evaluate the performance under different environments, different growing conditions and different levels of maintenance.
NG Turf has been testing some new bluegrass varieties from Texas A&M.What has the grass been through by the point it reaches testing by a sod producer?
So by the time a potential variety gets to NG Turf, it has likely gone through years of evaluations for turf quality, stress tolerances and relative comparisons to other commercially available varieties as well. From that research, the breeder is able to make recommendations on what we can expect when these grasses are planted in our region.
NG Turf has seen the research and followed some of the recommendations that are being made with some of these new varieties. They’ve been doing some in-house research as well, just looking at the relative performance of some of the new bluegrass varieties compared to tall fescue and also warm season grasses and they see a real opportunity for these grasses to be introduced to Georgia and throughout the transition zone.
How are care and maintenance recommendations developed for new turfgrasses?
We test different levels of maintenance, whether it be mowing height, cultural practices, fertility levels, tolerances to shade and other stressful conditions for grasses. Multiple years of multiple grasses undergoing scientifically sound experimental designs and replications result in data to help support some of the recommendations going forward.
There are always industry standards that these new grasses are compared to, so growers can refer back to what’s currently being offered to turf managers and show the improvements or benefits of some of the new varieties that are being introduced.
How long have you been working with NG Turf on the new bluegrass varieties?
I came on board about four or five years ago when they were just planting some of their fields with those new varieties. Weed control research is my area of expertise, and I think it is one of the biggest concerns for producing new grasses and getting them out to the industry.
We need to make sure that the turfgrass is at the best quality possible. We need to know how to control weeds in these grasses and what the response and what the levels of safety will be with commonly used herbicides in the turfgrass industry.
The first couple of years, we were looking at establishment, what are the best ways to grow these grasses in and prevent weeds from establishing while we’re also trying to get the fields grown in at the same time. We were looking at different pre-emergent herbicides, post-emergent herbicides, various application timings relative to the maturity of the grass in the fall and the wintertime.
Right now we’re looking at weed control programs for sod growers that could also be used by end users once they have grass planted for their turf, so looking at herbicide programs that will offer good selectivity for targeting problem weeds in the summer but will also offer good safety for the hybrid bluegrass in warmer temperatures of spring and summer.
Are you also looking at cultural practices?
I am not in this round of research, but that is always something that will be important for end users, promoting the optimum growth of the bluegrass so that it can be competitive with weeds and also other pests. We will likely bring cultural practices into future research as we fine tune our recommendations on the tolerance levels of these grasses to pre- and post-emergent herbicides in the initial rounds of research.
Dr. Patrick McCollough
Dr. Patrick McCullough serves as a turfgrass weed scientist breeder at the University of Georgia in Griffin. He conducts weed science research and extension activities related to turfgrasses and teaches the weed science component of Turfgrass Pest Management.
McCullough earned a Ph.D. in turfgrass weed science at Rutgers University. He also earned an M.S. degree from Clemson University and a B.S. degree from Western Kentucky University.
