Total Landscape Care Digital Magazine
Issue link: http://read.dmtmag.com/i/217626
Debugging Grub Control If grubs seem just beyond your grasp,it's time to up your game. BY CINDY RATCLIFF I t doesn't take much digging to discover that grubs are a problem pest for turf managers throughout the United States. Given the expansive nature of grubs and the damage they can do, much time has been devoted to developing ways to control them, leading to some effective products. If you aren't getting rid of grubs, it's time to troubleshoot your technique. There are a variety of factors that can influence efficacy of products used for grub control, but there are three variables that are the most-likely culprits. If your results for control aren't what you expected, odds are it's because the product isn't watered in effectively, the active ingredient isn't appropriate or the timing is off. Keep in mind, though, your standards of control might need an adjustment, as well. In general, mortality in excess of 60 percent is considered to be adequate to drop the white grub population below the injury level and thus accomplish the goal of the application, according to the University 12 To t a l L a n d s c a p e C a r e . com D E C E M B E R 2 013 of Illinois Extension. But it's possible to boost that percentage by optimizing application timing and technique. Damage control Initial signs your client may have grubs or that a treatment has failed are often revealed in spring as turf begins to green up. If you see bare patches, you'll want to sample for grubs. Healthy turf can withstand a low population without evidence of damage up top, especially during a rainy fall or spring. But 10 to 12 grubs per square foot generally are enough to cause visible damage to turf. Just add water Getting grub-control products to the root zone where the larvae are feeding is a critical component to treating them successfully. In fact, it could be the most common missing link between a hit or miss, says David Smitley, professor of entomology PHOTO COURTESY OF DAVID CAPPAERT, MICHIGAN STATE UNIVERSITY, BUGWOOD.ORG chemical care