Getting the most out of the new stuff

In her nearly two decades at Rutgers University, Dr. Stacy Bonos has had a direct hand in the evolution of turfgrass science, specifically on the development of new cultivars of bentgrass.

Thanks in part to her work, superintendents looking to convert their facilities to bentgrass or regrass with a state-of-the art strain have an abundance of varieties to choose from. Presently there are perhaps a dozen new cultivars of bentgrass available for use on greens and half that number available for fairways.

Speaking at the recent New Jersey Turfgrass Association Green Expo, Bonos noted that superintendents must consider a number of factors when choosing a strain of turf for their facility. Climate, soil conditions, topography and disease susceptibility all factor into the mix. Cost, of course, is an important factor. But Bonos says a bigger upfront investment for a higher quality of seed will save money over time.

“You could probably go with the cheapest variety,” she says. “But you’re probably going to be paying for it in the long run with additional fungicide applications. You could probably pay for the cost of the seed with one application or perhaps two of a fungicide on your golf course. So it really pays to pay the higher price for a better variety and in the long run it will pay you back with less input.”

Bonos, a Rutgers assistant professor since 2001, recommends superintendents start planning two or three years out before switching to a new or different strain of turfgrass. She also advises testing a new strain in a nursery before committing to installing it on the golf course. Bonos cites today’s modern strains of bentgrass for their resistance to disease, specifically dollar spot.

“When I first started working on this, all of the varieties that we looked at were susceptible (to dollar spot),” she says. “There was nothing that was resistant completely; there really is still nothing that is completely resistant but we really have made dramatic improvements, to the point where there are varieties that can be sprayed with almost 60 to 70 percent less fungicide applications than the standard older varieties that are more susceptible. So I think we are making pretty good strides in that area.”

Bonos says today’s modern strains of turfgrass stand up against other diseases as well, such as brown patch. “Brown patch is interesting,” she says, “because it doesn’t necessarily kill the grass. It looks bad for about a month or so but it doesn’t kill the grass like dollar spot will. And dollar spot is much more prevalent and longer lasting through the spring, summer and fall. Brown patch is really a problem only in the heat of the summer, in July and August. But it’s still unsightly, so you want to have a variety that’s got some good tolerance for that.”

Bonos also deals with copper spot, something that most superintendents don’t encounter.

“(Copper spot) reminds me a lot of pythium,” she says, “because it comes on really quickly. It’s got these small orange spots and it can come on very quickly and really damage your grass. But typically you don’t see it when you’re spraying preventatively. We don’t spray preventatively in most of our trials and we do see it. And it’s not related to dollar spot resistance so you could have a variety (of turfgrass) with good dollar spot resistance that is susceptible to copper spot.”

While dollar spot draws much of her attention, Bonos and her colleagues are continuing their efforts to develop grasses that will stand up against a variety of diseases. Achieving that goal reduces the number of chemical applications that are necessary.

“The main thing I would say is we work on dollar spot,” Bonos says. “Then we add brown patch, then we add copper spot, then we add anthracnose. We’re trying to get varieties that are resistant to multiple diseases and not just one, so we can really have try to have an impact on the amount of fungicide that’s being applied on golf courses.”