Making Money From Grubs: Grub Control

When a group of lawn care operators talks about controlling insects, grubs are likely to be one of the first turf pests to come up in the conversation. The combination of how much of the country battles grubs every summer and the extensive damage these insects can cause certainly makes them one of the most important factors in a lawn care season.

The strategy contractors employ to treat grubs is one of the common topics of discussion, and varying approaches can be a point of contention with some people.

Traditionally, grubs have been managed through a variety of curative methods, but this approach could be a gamble for contractors in the event they are too late or not suitably effective with their curative products. In either case, the result would be a damaged lawn.

Insecticides brought to market in the last few years have swayed many contractors to shift to a preventive grub control program. The downside to this approach, according to some industry personnel, is that lawn care operators can never anticipate with 100 percent accuracy the areas that will present grub problems. As a result, broad applications of the insecticides are made and more product will be applied than is ultimately necessary.

"What approach is better depends on your perspective," remarked Kevin Mathias, turfgrass advisor with the Institute of Applied Agriculture at the University of Maryland, College Park, Md. "If you are talking about Integrated Pest Management, then a curative approach is better because then you’re monitoring for pests and treating areas that need to be treated. The problem associated with a curative approach, however, is that the products used are broad-spectrum organophosphates or carbamates that also tend to knock down the natural grub predators and present more environmental issues and applicator issues than the preventive products do."

A curative approach also requires some effective customer communication.

"If your customers don’t mind a little damage, then you could take a curative approach," noted Neil Cleveland, turf and ornamental market manager, Bayer, Kansas City, Mo. "But customers must agree up-front to keep their lawns properly irrigated and to call at the first sign of damage."

"If you apply the preventive products, you might avoid some of those problems associated with curative products, but you will probably apply more product than you need to," Mathias added.

NEWER CHEMISTRIES. Changes in how contractors approach grub control have come about due to the development of two new products – halofenozide, which is marketed under the name MACH 2 from RohMid, Parsippany, N.J., and imidachlorpid, which is marketed under the name Merit from Bayer.

Both MACH 2 and Merit have been well received and praised by the market and researchers for their environmentally friendly nature as well as their performance.

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"One of the reasons the market has shifted to the preventive products is that there are so few of the curatives left," observed Fred Baxendale, entomologist, University of Nebraska, Lincoln, Neb. "Oftanol, Triumph and Turcam have all been taken off of the market, and now we have these effective preventive products that go down at such low rates and are much more environmentally benign."

In addition, MACH 2 and Merit should be joined on the market in the near future by Meridian from Novartis Turf & Ornamental Products, Greensboro, N.C., which is also receiving favorable early reviews.

"Grub control service is usually an optional service that contractors can sell separately to their clients, giving them the opportunity to pass along the higher costs of these preventive insecticides to the customers," noted Baxendale. "The increased competition should bring down the price of these products in the future to some degree."

"When customers understand the result, a healthy green lawn, they will accept the charge for grub control," added Cleveland. "This is especially true when the LCO supports the sale with a guarantee."

MAKING GRUBS = MONEY. Contractors don’t express a great deal of concern over the downsides of preventive grub control or the higher prices of the products.

"Our preference is to offer preventive grub control, but that’s largely because if there was a season with increased grub problems we wouldn’t be able to get to all of our properties and treat them right away," reasoned Gil Chappell, president, Lawn Pro of Kansas City, Lenexa, Kan., adding that about 80 percent of his customers buy the grub control service. "We offer the service as an option to our customers, but more of our competitors are including the preventive treatment as part of their basic program."

Chappell, who said masked chafer pressure was relatively light in his area in 1999, recognizes a preventive approach does at times call for applications that aren’t actually necessary, which he said is one benefit of making the service optional to customers.

"We have some customers with shady lawns that are very unlikely to have grub problems, so I don’t see any sense in selling them a service they don’t need," he noted. "For those properties that do buy the grub control, we figure the cost on a square footage basis and we normally apply the insecticide in conjunction with another service so we’re not making an extra trip."

While the rationale behind making these combination applications is obvious and sound, some researchers caution landscape contractors to make sure they understand the purpose of each application they are making and not let a desire for productivity negatively affect their scheduling.

"I get nervous when I hear about contractors putting preventive grub control products down in mid- or late April simply because that timeframe coincides with one of their other rounds," related Baxendale. "Making the application too early is asking a lot even of products with 120-day half lives if the expectation is for that product to be full strength in July.

"If contractors make these early applications and then run into a particularly wet spring, a summer that is particularly dry or a particularly heavy grub population, then there is an increased likelihood of the product failing," he continued. "The more out of sync you are with the application timing, which generally means making the application too early, the more cautious or vigilant you have to be in your monitoring late in the season."

Before going with earlier applications, Baxendale recommended picking one or two properties that can be monitored as test plots to see how the product holds up through the season. Then these lessons can be applied the following year.

MAKING THE MOST. Any contractor applying any pesticide wants to maximize that application’s effectiveness. Timing insecticide applications correctly is certainly one method of doing this and is primarily a concern with the preventive products since timing curative products is easy to do.

"We know the life cycle of the masked chafer, which is our primary grub in this area, and its adult population peaks around July 4," observed Chappell. "So most eggs should be hatched within four weeks of that time."

But, in addition to the grub life cycle, Chappel has learned to consider the insecticide’s effect on other pests and take those results into consideration for timing his application, which is a lesson Baxendale thinks more contractors need to learn.

"We used to apply our preventive product in late June or early July, but we’ve moved the dates up in some cases because we have some billbug problems that occur earlier," Chappell noted. "Now we treat our warm-season grasses in May."

"We’ve been looking at the concept of multiple pest control with one product, and we’ve found that different products are effective with a range of insects," related Baxendale. "That means a late May application of a preventive insecticide could have some control of billbug, first-generation webworm and then provide grub control.

"But too many contractors think of these products as grub control products because those are the key pests that they design their control programs around," Baxendale continued. "And we always want to remind contractors there are other pests out there besides grubs. They can’t just put down a grub control product and rest easy."