Identifying and Controlling Pesky Pests
|By ROBIN WESTMILLER|
AS A LANDSCAPE CONTRACTOR, AS IN ANY BUSINESS, YOU’RE constantly looking for ways to increase your client base. Of course you provide the very best in design/build and maintenance services, or just maintenance itself, but so does your competition. While you’re looking at the big picture, and your bottom line, you might not see the “trees for the forest” or, in the case of a landscape project, the blades of grass for the lawn. But look close—really close—and you will discover a golden opportunity staring right back at you, chomping on the shrubs, devouring the leaves and crawling in the soil.
If you can spot insects and grubs, and the damage they’re causing, your client can spot them, too. The question is, who are they going to call to solve the problem?
Whatever action they take, whether it’s driving to the local hardware store to purchase an over-the-counter pesticide or calling a pest control company, they’re invariably giving their business and money to someone other than you.
Your business is more than maintaining the turf and the landscapes. It’s also about maintaining your relationship with your client, as well as your reputation. By adding pest, weed and disease control application services to your company’s repertoire, you’ll be providing an additional service, and one less competitor to solicit your client.
Landscape perfection begins with the lawn. All the hard work you put into the walkways, trees, flowers and fountains won’t matter if your client’s turf is being destroyed by an insect infestation. To keep your client’s landscape looking beautiful, it’s necessary to control turf-impacting pests.
Let’s take a look at some pests that are prominent in landscaping, the damage they cause and finally, how they can be controlled.
Grubs are a common pest in turfgrass. They are the larval stage of many different beetles.
During the warm summer months, the female adult burrows around three inches into the ground to lay her eggs.
As soon as they hatch, these grubs start eating by sucking on plant roots and continue sucking the juices until the turf dies.
Signs of grub damage are fairly easy to notice. If you spot irregular patches of brown on a well-watered lawn, there’s a good chance that area is infested with grubs. The soil will also feel spongy and loose to where you can easily roll back the sod like a carpet. When the turf is lifted to expose the grubs, they usually will be lying on their sides in a C-shaped position.
When it comes to controlling a grub infestation, timing is crucial. Grub elimination should be timed to target them at the youngest stage when that are close to the surface.
“The story of grubs starts with a 4th of July party,” says Tom Kroll, technical services manager, NuFarm Americas, Inc., Chicago, Illinois. “The best way to control grubs is to apply insecticide just before the eggs hatch. That window of opportunity is usually three weeks prior to July 4th, from up to two weeks after July 4th.”
Kroll recommends using an insecticide with the active ingredient imidacloprid in either dry form, which can be applied with a spreader, or as a liquid, which is sprayed on. Chloraniliprole and Trichlorfon are other active ingredients that are effective.
Another insect common in turf settings is the chinch bug. Chinch bugs rapidly kill turf once they’ve become established. Although they don’t attack all grasses, some of the most common warm- and cool-season turfgrass species are likely chinch-bug targets. Most of the varieties of grasses thrive in the Sunbelt states.
Chinch bug damage is usually first detected when irregular patches of turf begin to turn yellow, then straw colored. These areas turn reddish brown and eventually die, while the chinch bugs move on to healthy turf. A yellow halo around the damaged area is typical of a chinch bug infestation.
The female lays its eggs, and as the eggs hatch the young chinch bugs, called nymphs, do the damage. Nymphs are yellow upon hatching, but soon turn red and have a light-colored band across their abdomens.
Chinch bugs suck on grass juices while releasing a toxin that causes yellowish to brownish patches in turf.
Over the years, chinch bugs have become resistant to almost every chemical used to control them, but insecticides containing bifenthrin have been shown to be effective, because the chemical works both internally and externally. “Bifenthrin kills the chinch bug both when the bugs ingest plants that have been treated with the chemical, and also when bifenthrin gets on their skin,” says Adam E. Manwarren, turf and ornamental product manager at FMC Professional Solutions.
You could apply the insecticide to the affected areas, or around the border of the landscape, but because they can fly, it’s difficult to keep an area totally free of chinch bugs. Manwarren recommends a broadcast application on the entire lawn with either a liquid spray or granular spreader.
While chinch bugs are annoying pests, they are strictly vegetarians. Much more than a picnic crasher, fire ants are an invasive species whose bite is extremely painful and potentially deadly.
Before attempting to treat for these ants, you must first identify them correctly.
Identifying fire ants is difficult because they look much like ordinary ants. They’re 1/8 to 1/4 inch long and reddish brown to black in color. Their bodies look like ordinary ants in that they have three sections: head, thorax, abdomen; three pairs of legs, and elbowed antennae, but usually the head will be a lighter color and the abdomen will be much darker.
They can also be identified by the distinctive mound-shaped nests they build. The fire ants’ mounds are at least 12 inches in both diameter and height, although they can be as large as two feet high and two feet wide.
Late August through early October is an ideal time to apply fire ant bait to lawns, but baits are slow-acting and can take weeks to months to reduce ant mound numbers. Applying pesticides, which use a combination of the active ingredients bifenthrin and zeta-cypermethrin, directly to the mounds have been shown to be effective in killing fire ants in less time.
What makes a fire ant colony difficult to destroy is that the nests can contain several hundred-thousand ants.
About 16 states in the U.S. have reported some level of fire ant problem, but California seems to be the sole state of choice for the Myoporum thrip. It’s named for the Myoporum ground covers and tree species which are widely planted in Southern California, due to their minimal water requirements and ease of maintenance. These imported pests were first discovered in Orange County, California, in 2005 and have rapidly spread to many different parts of the state. The thrip insect is smaller than one millimeter and often hides in curled up leaves or within buds of flowers. It is yellowish brown or black in appearance, but can have brightly colored spots as well. There are many different species of thrips, but they all share some common features, such as thin bodies, feathery-looking wings, and elongated feeding tubes that are used for puncturing and sucking.
The Myoporum thrip attacks the flowering shrub Myoporum by sucking the plant’s juices to the point the plant dies. While much is known about thrips in general, little is known about this particular pest of Myoporum. Early studies by James Bethke and David Shaw of the University of California found that two applications of imidacloprid or spinosad reduced the number of thrips and the amount of damage to infested Myoporum plants. Further research is continuing to ensure the insects don’t migrate to other states.
Also limited to a small portion of the country, the ficus whitefly is causing a great amount of damage in South Florida. Ficus trees without their leaves are one of the most obvious symptoms of a whitefly infestation. “In Florida, ficus are used as privacy hedges because they can grow anywhere, are between five and eight feet tall and totally block the neighbor’s view,” says Todd Mayhew, western field development manager, Valent Professional Products, Walnut Creek, California.
“This particular whitefly gets on ficus and sucks out the juice, causing the plant to lose its leaves. If you have a privacy hedge with no leaves, it sort of defeats the purpose.”
Whiteflies are small, winged insects that typically feed on the underside of leaves with their “needle-like” mouthparts. They can seriously injure host plants by sucking juices from them, causing wilting, yellowing, stunting, leaf drop or even death.
The adult whitefly resembles a very small moth, with a yellow body and white wings with a faint gray band in the middle of the wings. Eggs and nymphs can be found primarily on the underside of the leaves.
The recommended method to control the whitefly is to drench the soil around the base of the tree or hedge with a product that contains a neonicotinoid compound. If applied appropriately, it should provide sufficient control of the whitefly for four to eight months, or perhaps longer, depending on the size of the tree or shrub.
Unlike the whitefly’s limited location, billbugs can be found throughout the entire U.S. Billbug damage usually appears in late June through August, when summer drought stress is common. Light infestations in lawns often produce small dead spots that look like the turf disease. Heavy infestations can result in complete destruction of the turf, usually by August. The major problem with billbug damage is that it looks like a variety of other problems, such as drought, disease, chinch bugs, or grubs. Billbug-damaged turf turns a whitish-straw color rather than the yellow caused by greenbugs. Soil under the damaged turf is solid, not spongy as in white grub attacks.
Billbugs are some of the most difficult turfgrass insects to control, because the adults’ armor-like bodies protect them from absorbing insecticides. They also don’t ingest much insecticide when they penetrate a grass stem while feeding. A systemic pesticide that contains the active ingredient dinotefuran can control billbugs, as well as a broad spectrum of other insect pests. With light to moderate infestations, much of the damage can be controlled with adequate irrigation and fertilization; however, with increased regulations on both irrigation and fertilization use, billbug damage is on the rise.
Integrated Pest Management (IPM)
IPM is not a single pest control method but, rather, a series of pest management evaluations, decisions and controls. By combining information on an insect’s life cycles and the way they interact with the environment, along with selected pesticide methods, IPM not only can eliminate an ongoing infestation, but can prevent one before it starts.
The options can be as simple as removing the pests with a garden hose, changing the watering schedule or modifying mulching. If these methods are ineffective, then it’s time to step it up a notch. Introducing natural predators into the infected environment or using non-chemical pesticides are two viable alternatives.
Biopesticides are a type of pesticide derived from natural materials. For example, canola oil and baking soda have pesticidal applications and are considered biopesticides.
Microbial pesticides are another type of biopesticide, made from microorganisms. The most widely used microbial pesticides are strains of Bacillus thuringiensis (Bt). After the pest ingests the chemical, Bt proteins paralyze their digestive system, and the infected insect dies from starvation.
Chemical insecticides are used in IPM as well. In many instances, the operator will isolate where an infestation is and spray insecticides only in that specific area. Integrated Pest Management is an excellent approach to insect problems.
Before adding pesticide application to your company’s list of services, it is advisable to check with your state’s Department of Pesticide Regulation, or similar agency, to see if a license is required. Some states offer a simple commercial ground applicator’s license, while others have commercial pesticide business licenses available as well.
While you won’t be able to totally eradicate all insects from the landscape, you can control and manage them. Whatever method you choose, your clients will be pleased that the next time they look closely at their grass, the only thing they’ll see is lovely, healthy green leaves.