With the news filled with stories about Rocky Mountain Spotted Fever, Lyme disease and other problems caused by the varieties of ticks that abound in the world, it's important to consider ways to control these tiny parasites.
The Health Issues
Ticks are most problematic in warm, humid regions, but they are a habitual seasonal problem in many temperate regions, as well. All ticks feed on the blood of host animals—mostly warm-blooded mammals but sometimes also fish, amphibians, and reptiles.
To humans, the blood-feasting habit is repulsive at best—especailly that of the so-called wood tick that forms a little sack of blood when it latches onto the skin of a pet or human. But some varieties of ticks are also known to be the vectors of at least 12 blood-borne diseases, including Lyme disease, Rocky Mountain Spotted Fever, Anaplasmosis, typhus, and several very serious hemorrhagic viral diseases.
Pet owners often seek a means of controlling the pests in their yards without preventive medicines or chemical applied to their pets. And in regions where Lyme disease or Rocky Mountain Spotted Fever is a problem, killing ticks in your yard would be a great boon. In many regions, gardeners have given up their beloved hobby because they are plagued by the bites of deer ticks, the carriers of Lyme disease.
Basic Tick Biology and Terminology
Ticks are parasitic members of the arachnid class of animals—the same animal family that includes spiders and mites.
It's specifically the black-legged tick (Ixodes scapularis) that can transmit Lyme disease, so if you live within its range (Eastern North America into the upper Midwest), this type will be your biggest worry. Ixodes scapularis can be transported into your landscape by deer or other hooved mammals, such as moose.
Deer are such a common source that the parasites are commonly called "deer ticks."
Much of the information here is relevant to controlling other types of ticks, as well, including the varieties that can transmit Rocky Mountain Spotted Fever and other diseases.
Any chemicals designed to kill ticks is a form of pesticide termed an "acaricide." As you can infer from the name, these chemicals will also kill other creatures within the arachnid class—which might be a consideration if you are wondering about chemical controls.
Types of Tick Control
The recommendations for tick control in yards fall mainly into three categories, and they may overlap somewhat. You can:
- Modify your behavior
- Modify your yard
- Try to kill any ticks that may live in your yard
Let's look at each of these approaches to control in some depth.
Modifying Your Behavior
One possible course of action is to protect yourself each time you enter tick-infested habitats—which could very well include your own yard. Ways to do this might involve:
- Spraying yourself with repellents
- Wrapping yourself in clothing from head to toe, and taking such measures as tucking the bottoms of your pant legs into your socks
- Wearing tick-repellent clothing
In addition, when you return from your outing, you should scan your body for ticks. You may need help doing this, as it's hard to inspect the center of your back or head without assistance.
These methods have limitations, of course. Spraying and bundling up for every outing is time-consuming and uncomfortable. Wearing sleeves and long pants tucked into your socks on hot days is unpleasant, and oily repellent sprays can be irritating to the skin. Tick-repelling sprays applied to the body commonly contain DEET, a chemical that is controversial, at best.
Modifying Your Yard
If you're gearing your efforts specifically to the control of deer ticks in order to minimize risks of contracting Lyme disease, one of your objectives should be to keep deer and similar animals away from your landscape, lest they bring Ixodes scapularis with them.
Three common ways to achieve this goal are through:
More generally speaking, experts recommend creating an environment in your landscape in which ticks are less likely to be able to survive. Ticks basically need two things:
- A host upon which to feed (in addition to deer, common hosts are pets, rodents, and birds)
To the degree that you can eliminate or minimize those two things, you can also reduce the probability of a tick infestation.
Certain changes in landscaping practice can also help. For example, you can modify your yard so that you won't be regularly brushing up against shrubs when walking along pathways. Dense groundcovers can also harbor ticks. A neat, tidy yard with dry conditions and no wildlife holds no appeal for ticks.
The last method, if you can't modify your behavior or your landscape to the necessary degree, is to consider chemical means of killing ticks. This is an option of last resort for most people, due to the inherent risks of chemical use. Although there are so-called "organic" pest controls, few of these are very effective against ticks. And even organic pesticides have some environmental impact. They may, for example, be so much less effective than synthetics, which means that they require many more applications. They are also much more expensive than many synthetic chemical pesticides.
If you do reach for chemical methods of controlling tick populations, you will need to consider whether to opt for synthetic chemicals or to try an organic pesticide. You'll also need to consider application methods and timing for the chemical application.
The CDC (Center for Disease Control), in an article titled "Natural Tick Repellents and Pesticides," recommends biological agent-based products that contain a fungus (Metarhizium brunneum/anisopliae) as the active ingredient. Specifically, the CDC states that these products are EPA-registered, commercially available, that they kill black-legged ticks, and are intended for use on lawns and gardens.
For example, there is a product called Met 52 EC that comes in an 8-ounce bottle.
Synthetic Chemical Acaricides
If you are not committed to staying "natural," one a chemical product that kills ticks (and many other bugs) is Onslaught® FastCap Spider & Scorpion Insecticide. With active ingredients including Esfenvalerate, Prallethrin, and piperonyl butoxide, it works by disrupting a pest's nervous system.
The correct place to apply an acaricide is along border areas, where a potential tick habitat (woods, brush, etc.) meets your lawn. Spray several feet into both sides of such a border (that is, into both the woods side and the lawn side). This practice is termed "perimeter spraying." The best time of year to spray is when the ticks are in their early nymphal stage. For deer ticks, this means spraying in May or early June.
There are different ways to spray for ticks. Before deciding to do it yourself, you are well advised to consider calling in a pro. Professionals will have more powerful spraying equipment, allowing for better penetration of the acaricide, and they know how to safely handle the chemicals.
But if you wish to kill ticks on your own, you may do so using:
- An RTU product (ready to use; attaches to garden hose)
- An RTS product (ready to spray; comes in a pump bottle)
- A spray that you mix yourself (apply with your own pressurized sprayer)
The chemicals are all the same in these products, so the choice will depend on your preference. Chemicals you mix yourself and apply with your own garden sprayer have some built-in risk of contact with chemicals as you pour and mix, but this can be by far the least expensive form. Ready-to-spray chemicals are somewhat expensive, but they eliminate the need to mix chemicals by hand. Ready-to-use products that attach to a hose are best for spraying very large areas.
Drawbacks to Chemicals
Any pesticide comes with one enormous liability, in that it will kill other creatures in addition to the targeted pest. If you apply a truly effective targeted acaricide that kills ticks, for example, you will almost certainly also kill helpful spiders that may be feeding on noxious insects, such as mosquitoes. And any birds that might be eating ticks and other spiders will then be denied one of its food sources. And if you are applying a more broad-spectrum pesticide, you may well be killing a great many beneficial insects, such as honeybees, ladybugs, and mantises. Genuine gardeners need to think long and hard about using such chemicals.
Human health hazards should also be considered. Be very, very careful when mixing chemicals, and wear protective breathing masks when applying so you don't breathe in the chemically laden mists. Manufacturers of pesticides may downplay the human health hazards, but it is best to treat all such products as extremely toxic. Some pesticides once regarded as safe (DDT is one example) have later been determined to be quite poisonous.
If you are environmentally conscious, you may first want to try organic methods, combined with the behavior and landscape modifications described earlier. If you do apply synthetic chemicals, limit the application area to border areas surrounding your yard, and avoid wide-spread broadcasting of these chemicals across your entire lawn and yard.