Preventive grub control appears promising in 2005

During the past decade, there has been a significant change in the chemical arsenal for white grub control and a shift in control strategies from curative to preventive applications. Presently, turf professionals should be optimistic about their battle with grubs because the current products and control strategies appear to be working. Moreover, significant new grub control products with potential advantages recently have been introduced to the turf market.

Currently, Merit and Mach2 are used widely for white grub control. But whenever control products have been available for a significant time, end-users begin to worry about loss of effectiveness. However, Merit and Mach2 continue to perform reliably in objective university trials when applied during their optimal control windows.

For 2005, two new products are available for white grub control with added-value features. One of these, Allectus, is a joint offering from Bayer and FMC, and contains the active ingredients of Merit and Talstar. By combining these actives for surface and sub-surface insects, Allectus will offer a single-product solution to many turfgrass insect pest problems. Product expectations are backed by more than a decade of research on each component.

The other key introduction for 2005 is Arena from Arvesta, a company that is known in the U.S. agricultural market and an emerging provider to the turf industry. The active ingredient in Arena is clothianidin, which is in the same neonicotinoid class of chemistry as Merit, but with a different activity. Arvesta describes Arena as a second-generation neonicotinoid, the significance of which includes lower effective use rates and a wider-pest spectrum. This product is available in granular and water dispersible granule forms.

Data released by Arvesta (Table 1) from 2004 grub trials at state universities tell a compelling grub control story, with Arena providing control equal and sometimes better than the standards. Also notable is the product’s effectiveness on the more difficult-to-control European Chafer and Oriental beetles. Regarding grub control timing, Arena also looks good in initial trials, giving better than 92 percent white grub control when applied in May, July or September. However, because the limited number of timing studies, more work is needed to firmly establish efficacy with respect to early and late application timing. Arvesta is currently conducting additional university trials.

Good control of other key turfgrass pests, such as the sod webworm and black turfgrass ataenius (Table 2), completes the picture of a product with potential to be successful in the turfgrass market. Arena is the first neonicotinoid insecticide with activity on caterpillar pests, according to David Shetlar, Ph.D., from The Ohio State University. Furthermore Shetlar says that in his trials, this material has performed as well or better than Merit and Mach2 overall – and at lower use rates.

New chemicals are in the research pipeline currently, notably from the neonicotinoid class of chemistry. Furthermore, university researchers are searching for biological control agents of white grubs that are effective and practical alternatives to pesticides. Golf and lawn-care professionals have good reasons to be optimistic about current and future grub controls.

Information from The Ohio State Univeristy’s March 2005 “Insect and Insecticide Update, Columbus, OH” by David Shetlar, Ph.D., was used in this article. Those interested in this or other presentations by Shetlar can access them on his Web site http://bugs.osu.edu/~bugdoc/.

Mary Ann Rose, Ph.D., is a consultant to the turf and ornamental industry.