Bad Bugs: Indian Meal Moth

by Alain VanRyckeghem, BCE Technical Director

What is the most critical damage caused by Indian meal moths – individually or as a whole?

Indian meal moths (IMM) either directly consume the stored food product, (bird seed, pet foods, candy bars etc.) and contaminate it with their presence, webbing, and waist products, or they indirectly contaminate product (food and nonfood) in storage from wandering larvae in search of pupation sites. One infested package of product can be a source of larvae that search out other food products to continue feeding or usually to pupate on the surface or interior spaces of the packages. Perfectly sealed packages that contain baby formula, for example, may have no infestation, but the presence of larvae on the container will cause consumer complaints and rejection of the product. This is essentially collateral damage from another food product.

Why is monitoring for IMM crucial, and what is the best way to monitor?

Monitoring for IMM is designed to be an early warning system. Detection of a couple of moths early in the season can help prevent or reduce further outbreaks during the summer and fall. Traps with sex pheromones to attract male moths are a tool that can operate 24 hours 7 days a week and can be placed in any environment. Placement can be in a grid system to detect recent invasions or can be targeted (concentrated) to monitor selected storage areas or help pinpoint the infestation.

Moth traps need to be monitored weekly, due to the trap’s short life cycle. The objective is to detect sudden rises in catch rates indicating a recent introduction of infested product or a sanitation issue that has been overlooked. Lure and traps are to be replaced according to manufacturer’s recommendation which is usually 8 weeks. All traps and lures should be replaced at the same time. Do not stagger the replacement schedule as this leads to old lures stationed beside new lures, resulting in misinterpretation of the source infestations.


What are the steps that should be taken if IMM are detected?

If IMM are detected, inspection of product near the monitors with most activity is necessary. Flashlight inspections to find active larvae, webbing, and food spills are the primary goals of the inspection. Detection of insect activity will require movement and segregation of the product for further action. This may include cleaning, disassembly, fumigation or disposal. Pallets with insect activity should be covered with a PE pallet cover before moving to reduce accidental dispersal to uninfested areas. Sanitation issues should be cleaned up and discarded outdoors in an approved dumpster system. Continue monitoring traps at the area of original activity and adjacent traps. Further activity will require repeated inspections.

How can IMM moth infestations be prevented?

The first line of defense to prevent infestation of a facility is to stop infested materials from being accepted at the receiving areas. This requires receivers to be aware of the presence of webbing on boxes or bags, live and dead larvae in the stretch wrap, and live moths flying out of the trailer or off a pallet. These are clear signs of activity and should not be ignored. Detailed inspection can locate these products with activity and should be rejected. The potential use of a pheromone trap in the trailer placed by the vendor at the time of shipment can also give an early warning to the receiver if this trailer has moth activity.

Is there anything else I should be aware of about IMM activity?

Indian meal moths are temperature dependent. Moth flight and reproduction usually does not occur when the environment is below 64 °F. The absence of Indian meal moths in pheromone traps in cool warehouses or cold trailers during shipment is not a fool proof way of determining if moths are present or if larvae are actively feeding on stored product in storage. At these times, a proactive inspection program by the PMP or in house sanitarian is recommended.

Bad Bugs: E-ntomology

By Alain VanRyckeghem, BCE
Technical Director

New technology helps identify the smallest pests in the field.

Stored product beetles are among the most difficult beetles to identify in the field. Very small features need to be observed in order to separate the common and serious beetles from the less important ones.

The pest control technician is often faced with separating two similar beetles such as: Red flour beetle (Tribolium castaneum) from the confused flour beetle (T. confusum); the saw-toothed grain beetle (Oryzaephilus surinamensis) from the merchant grain beetle (O. mercator); the cigarette beetle from the drugstore beetle; and the ever difficult Trogoderma species.

These beetles are very small and proper identification should be done under a microscope. A tool for field use is the palm sized microscope MiScope™. This device is connected to a laptop via a USB cord, and the image is displayed on the screen through software that comes with the microscope.

Excellent magnification is possible (40X–140X). The field of view for whole insects is between 2 mm and 10 mm; with larger insects, only portions of the specimen are visible. For small insects like the carpet beetles, the shapes of the scales which make up its varied colors are clearly visible at the highest magnification. Still photos or videos can be recorded on the computer and sent to knowledgeable entomologists for their identification.

The microscopes come in an affordable standard 1.3 mega pixel imaging unit for field use and a more expensive higher quality 2.0 mega pixel unit for lab/office use. The software has additional features that make it useful for publication such as the addition of a calibrated micron scale, contrast adjustments, drawing, and labeling.

Carpet Beetles Eat More Than Just Carpet

by Pat Kelley, ACE

The term “carpet beetle” is frequently used in reference to the little beetles and “worms”
that quietly munch away at rugs and carpets beneath our feet. The truth is that these beetles, in the family called Dermestidae, will eat a wide variety of materials. Their food can include processed food for human consumption, dead animals/insects, feathers, furs, and yes, they will also eat the natural fibers found in woolen rugs and carpeting.

The most common carpet beetles consist of these six species: Black carpet beetle, Attagenus unicolor; Brown carpet beetle, Attagenus elongates; Common carpet beetle, Anthrenus scrophulariae; Furniture carpet beetle, Anthrenus flavipes; Guernsey carpet beetle Attagenus sarnicus; Varied carpet beetle, Anthrenus verbasci.

The adult beetles become active in the warming springtime of temperate climates. They can be found feeding on the pollens of Spirea flowers as well as other flowering plants. Mating often occurs outdoor, after which the females come indoor looking for food sources on which to lay their eggs. An accumulation of dead insects in attics, window wells, ductwork, or in wall voids can attract the initial females as a good food source for her young larvae. The larvae can then transfer over to carpeting or other available food sources nearby. The larval stage does the most damage to stored goods as they are ravenous eaters. When inspecting for carpet beetles it always helps to “know your pest first.” By knowing the biology of the beetles and the wide potential of food sources for these insects, you now know that you need to look much farther than just the carpeting to find potential  infestations. Pheromone traps are available but are specific for each species. Larval dermestid monitors can be used to detect for the larval stage.

Reducing Customer Complaints: Excerpt

This is an excerpt from Reducing Customer Complaints by David Mueller:

Pest management is not about a “product.” It is about a path of continuous quality improvement. Stored products are threatened by pests from the time they leave the field to the time they are consumed.

The future generation will control pests by managing environmental conditions.

Insects are a symptom of a problem. The problem solvers and pest managers must interpret the clues that permit the conditions in which these pests thrive and control these conditions to discourage these unwanted guests.

If we begin with the insect or other pests first and study what they like and don’t like, we then can offer them an environment in which they are uncomfortable and will then leave or die.

Companies that put their brand on their products are selling more than just the product in the package, they are selling their reputation. Protecting this brand integrity is essential. The expectations of food purity laws and food safety standards are changing. Recently, highly published deaths and human suffering from food borne diseases will force manufacturers to review their food safety programs and make adjustments. It will force pest managers to be better than ever before.

Pest management is about long term solutions to pest problems. In the past hundred years it has been convenient to fumigate or spray away a pest problem only to have it come back in days or months. However, the conditions that caused the problem to occur in the first place remain. The survivors begin reproducing to restock the problem in a short period of time. These conditions still offer an optimum environment and will surely attract more pests from the surrounding area, including outdoors. Again, the long term solution is to identify and correct the problem and offer the conditions that the insects or other pests cannot survive in. They then will leave or die.

Fumigation Trends
A trend has occurred in the last two decades to contract pesticide applications in post harvest stored product protection to a select few specialized fumigation and food safety companies. General pest control companies that perform pest management and pest control for residential accounts have gotten out of the fumigation business for the most part. The cost of the license, minimum insurance, continued education, and capitol cost of new fumigation equipment, including expensive monitoring equipment, has eliminated the small player from this expensive, educational intensive and potentially high risk business. Fumigations are performed mostly on major holidays and weekends when the food plants are closed. In the past, most pest control companies carried fumigation and food processing licenses, but today only a few very specialized companies exist in North America.

This is an excerpt from the new book Reducing Customer Complaints in Stored Products by David K. Mueller. It is intended to help you solve pest problems in stored products.

Life of the Spider

by JH Fabre

J.H. Fabre became one of the greatest entomologists in history; not because he was a faculty member of a prestigious University like Oxford, Cambridge, or Harvard, but because he, like Darwin, was a great observer. He would sit for days and observe the habits of one insect or spider in a small lot near his home in rural France. His ability to communicate his observations in over a dozen books became a must read in the early 1900’s for children and adults. Napoleon III wanted to bring him to Paris to be the national scholar of France. Fabre refused the invitation and he returned home to continue observing and teaching.

Life of a spider

Fabre was one of the first scientists to recognize pheromones. He placed a small box with a female moth near a screened window in his lab. He observed several male moths, of the same species, actively flying on the outside of the screen. He was one of the first to observe and understand the effects of insect sex-attractant pheromones back in the 1880’s; about 100 years before modern scientists were able to identify their molecular structure, synthesize, and use them commercially.

Life of a spider 2

Here is an example of his poetic prose about spiders from his book called “The Life of a Spider” written in English in 1912:

“The Spider has a bad name: to most of us, she represents an odious, noxious animal, which everyone hastens to crush under foot. Against this summary verdict the observer sets the beast’s industry, its talent as a weaver, its wiliness in the chase, its tragic nuptials and other characteristics of great interest. Yes, the Spider is well worth studying, apart from any scientific reasons; but she is said to be poisonous, and that is her crime and the primary cause of the repugnance wherewith she inspires us. Poisonous, I agree, if by that we understand that the animal is armed with two fangs which cause the immediate death of the little victims which it catches; but there is a wide difference between killing a Midge and harming a man. However immediate in its effects upon the insect entangled in the fatal web, the Spider’s poison is not serious for us and causes less inconvenience than a Gnat-bite. That, at least, is what we can safely say as regards the great majority of the Spiders.”

The Pheromone Kitchen

by Alain VanRyckeghem, BCE

We are lucky at Insects Limited to produce most of our important insect pheromones in the lab and thus have control of inventory and quality of product going to the customer. Did you ever wonder what goes on in the pheromone synthesis lab?

It can be a lot like cooking in a kitchen. You can create a finished product like soup, but along the way there are several steps of preparation, cleaning, boiling, filtering, and of course tasting. Pheromones begin with raw (chemical) ingredients. The recipe to get from step one to step two may vary from one chemist (cook) to another, so it is the chemist’s choice of ingredients and how to combine them that can determine the quality, quantity, and chemical structure (flavor) at the end of each step. Chemists ‘taste’ the product along the way with a gas chromatograph. If that batch of product is substandard, it is thrown out (properly disposed of) and the process has to start over.

Sometimes the ingredients are boiled in order to combine them; other ingredients are frozen to -110°F before they can be combined because they will catch fire (now that is spicy!) Often we have to combine them under nitrogen (no air) again because they can catch fire. After completion of an initial product, it may be filtered to remove solids, or it could be distilled like whiskey to get the pure ingredient (alcohol, for example). The purity of the product is our most important factor before we move on to the next step.

Pheromone Kitchen

Some of the pheromones require only a ‘one pot’ assembly and the product is made in a day or two of mixing. Purification can take several more days afterwards. A few of our pheromones have several steps (from 6 to 15). The more steps there are the more costly the pheromone becomes because you get less and less after each of the purification processes. The glass pots we use range in size from as small as a shot glass to as big as a keg of beer.

Once the pheromone is made it is either used on its own or combined with other pheromones to make a blend that is specifically attractive to one or two insect species. Because of our on-site chemistry lab, we are able to manufacture pheromones for minor pests that most other chemical manufacturers will not do because of low volume. These include: Cigarette beetle, Hide beetle (8-pheromone blend), Varied Carpet beetle, Black carpet beetle, Furniture carpet beetle, Lesser and Larger grain borers, Rice weevils, Granary weevils, Angoumois grain moths, and, of course, our Clothes moth pheromones.