Holistic Pest Identification

Developing a proper pest management program depends upon correctly identifying the pest involved. By asking the right questions about the habits and/or habitat of a pest, you can often make a correct identification without ever seeing an actual specimen.

Before an effective integrated pest management program can be developed, it is necessary to know the pest or pests with which we are dealing. And identification is an integral part of any IPM program. This knowledge enables us to determine which control measures to employ and when, where and how to employ them. In addition, several states require that any chemical applications performed be for a specific pest and that this pest be listed on the treatment record.

While customers can often identify many pests by general categories such as cockroach, fly or rodent; they are seldom able to make a more specific identification. Such specific information is necessary so that the proper management program can be developed. Even though two pests may be of the same group or family, their food, shelter and habitat requirements may be quite different. In addition, the damage they may cause can vary greatly. Similar-looking beetles, for example, may damage wood members, stored products, carpets and house plants. Each requires a different control method. It is important, therefore, to be sure that the pest is properly identified.

A HOLISTIC APPROACH. The need to be effective, and in many states to remain within the law, requires that the pest control professional devote the time necessary to properly identify the pest or pests involved. This can often be accomplished by employing a “holistic approach to pest identification.” Simply put, this approach considers where, how and under what conditions the pest lives. By considering factors such as where it was found; what it was doing; its nest, web or lair; associated damage; and even how it moves, we can often tell what the pest is even before we see a specimen.

We learn this information by playing detective; by combining a thorough inspection with the right questions. And customers are often the best source of a great deal of helpful information. If we ask the right questions, they can often help us narrow our search and identify the pest. Sometimes, however, the customer is unable to provide all the answers. This is where the thorough inspection becomes crucial. It will provide evidence of the pest itself, as well as where it lives, how it lives and what conditions are enabling it to survive.

The holistic approach can be effective in enabling us to identify a pest long before we see an actual specimen. By developing a series of questions, we may use the customer’s observations to our advantage. For example, let’s assume that a customer calls to tell us they have found several small beetles. At this point they may be wood-destroying beetles, stored product beetles, hide beetles or an occasional invader. By asking where they were found, what they were doing, what they were feeding upon and if any damage was found, we can narrow down the possibilities. The presence of these beetles inside an old bag of flour, for example, quickly points toward a stored product pest and most likely a confused flour beetle. In cases where the customer does not know all of answers, we can often derive sufficient information from them to point us in the right direction. A thorough inspection will then help confirm our preliminary determination.

In addition, we often find that even though we have a specimen, identification is made easier when we’ve asked the right questions. Many pests look similar even though their habits, habitats and life cycles are vastly different. There are many species of dermestid beetles, for example. Depending upon the species, they may attack carpets, hides, stuffed birds, etc. The species determines the management program.

ASKING THE RIGHT QUESTIONS. The key to the success of a holistic approach to pest identification is asking the right questions. Initial questions should be general and the answers to these will determine subsequent questions. Then, a thorough inspection will confirm the initial diagnosis. There are 10 basic questions we should ask that will greatly increase the likelihood of a successful pest identification. The answers may be followed up with more specific questions to “fine-tune” the identification.

1. Where did you find or see the pest? The location of the pest is a critical first step. Was it indoors or outdoors? If outdoors, was it in close proximity to the building, in the lawn, near or in outbuildings? Was it in a tree or shrub? Location within the structure leads to the question of where inside it was found.

2. Was it on a surface, inside an item or piece of furniture, or in a food item? Where exactly was the pest? Although its specific location doesn’t necessarily imply its habitat, it can often be an effective inspection point. Obviously, a pest in a cabinet or more specifically, in a food item, can generally be expected to be living or feeding there. We can then thoroughly inspect this site and expand from there. If it was on a surface, ask if it was attached to the surface in any way, such as with silk or a sticky substance. It may be a web, cocoon, egg case or some other item.

3. What was it doing and when? Was it moving? Resting? Feeding? Emerging from a hole, a cocoon or other structure? Was it alone or were there others nearby? Did you see it during the daylight hours or at night? These questions can help determine the extent of the infestation. Cockroaches and/or rodents feeding during daylight hours, for example, indicate a heavy population that is well-established.

4. Did it have a nest, web, lair, or other abode, resting or hiding place? Often, although we don’t see an actual specimen, we see the nest, web or resting place. Just as a web immediately identifies the pest as a spider, other materials can help to identify pests. For example, mice will fashion bits of thread, cotton, insulation, grass and even shredded newspaper into a nest. Rats often create tell-tale burrows. Some pests, such as cockroaches indoors or earwigs outdoors, cluster into groups which, when located, can be eliminated.

5. Did it cause any damage to food, feed, furniture or structure? During the course of the inspection we can determine whether the pest has caused any damage. Frequently, the damage itself is a giveaway. Who wouldn’t be able to identify a pest that damages wood and fills the damaged galleries with mud? Or what about the pest that produces perfectly round ½-inch holes in decks and soffits? If the damage was to food, determine whether the pest consumed large amounts or small amounts, or if it damaged the box, bag or container. Were there exit holes? And what did they look like?

6. Did you find any fecal deposits, pellets, piles, residue or stains? Pests often leave various tell-tale signs of their presence in the form of deposits or stains. Droppings from rats, mice, squirrels, birds and bats can be identified easily. Rats also leave rub marks along frequently used runways. Piles of dust with dead insect parts can be readily identified as carpenter ant frass. Cockroaches leave easily recognizable fecal deposits. Ask the customer if they found any such evidence.

7. How did it move? How the pest moves can be an effective identifying characteristic. Ask if the customer saw it moving, and if so, how. Did it crawl, slither, walk, run, hop or move in some other fashion? Mites, ticks, bedbugs, carpet beetle larvae and many spiders crawl. Snails, slugs, snakes and larvae of many moths slither. Rodents, cockroaches, silverfish, ants and many others walk or run. Crickets and fleas hop or jump. If the pest flew, ask if it was a good flier or poor. Did it fly fast or slow? Could it hover, back-up, land on the ceiling or a smooth vertical surface? All of these movement patterns can help you narrow down the possible pest.

8. How many were there? Sighting only a single pest does not necessarily mean that others are present. It may have been a single individual that entered the structure in search of food or a place to “set up housekeeping.” The sighting of several individuals, however, usually indicates that they have established themselves. Notable exceptions to this are overwintering pests such as cluster flies, boxelder bugs and ladybird beetles. Asking the customer how many they’ve seen and whether they were all together or spread out over a great distance can indicate the degree of the infestation and the extent of its dispersal.

9. Did it bite, sting or pinch, or cause harm to persons or pets in any way? Ask the customer if anyone has been bitten, stung or pinched by the pest. Bites may be from mosquitoes, bedbugs, fleas, ticks, lice, spiders, ants and even rodents. Stings may be from bees, wasps, hornets and some ants. Insects that can pinch include large ants (such as carpenter ants) and beetles.

10. Do you have a specimen or can you give a brief description of the pest? The final question to be asked is whether the customer has a specimen of the pest in question or if they can at least provide a brief description. Be aware, though, that specimens provided by customers may be missing vital parts or be crushed or decayed. The presence of a specimen, however, should not replace asking the foregoing questions and performing the accompanying inspection. What a customer provides as a specimen may not be the actual culprit. Even if the customer provides an accurate specimen, it is still necessary to proceed with these questions to confirm the pest and identify its location, the size of the infestation, and any damage or injury it caused.

Pest identification, at best, can be a difficult task. A small moth missing its antennae, a few legs and most of its scales is tough to identify. But if we find out that it was on the floor of the closet and an article of clothing was found with holes in it, we might conclude it was a clothes moth. The same specimen found in the kitchen cabinet might be an Angoumois grain moth. Asking the right questions can provide us with the information necessary to properly identify the pest. Effective pest management is dependent, after all, upon proper identification.

Dr. Mark Lacey is eastern technical services manager for Paragon Professional Products.