Termites & Other Wood-Destroying Insects: Fact or Fiction?

Fact or Fiction? Subterranean termites feed only on wood.
FICTION! Subterranean termites will eat any material containing cellulose. Items containing cellulose include, wood, cardboard, paper, and some plant material.

Fact or Fiction? Although termites can consume almost any cellulosic material, they cannot actually receive any nutrition without the help of symbiotic microorganisms living in their digestive tract. FACT! Large numbers of microorganisms living in the digestive tract of termites break down the cellulose and release nutrients that can then be absorbed. As protozoa in the termite’s gut break down decaying wood, they generate carbon dioxide and hydrogen, which leads to the production of acetate (a source of nutrition for termites).

Fact or Fiction? Subterranean termites must maintain contact with the soil.
FICTION! Subterranean termites need a constant source of moisture to survive. Although subterranean termites normally remain in contact with the soil, if conditions are suitable (i.e., there is sufficient moisture + wood), then termites can remain aboveground.

Fact or Fiction? Termite workers are both male and female.
FACT! The termite workers are both male and female but they are functionally sterile. Workers are the caste that damage wood.

Fact or Fiction? A termite nymph (the stage that hatches from the egg) may molt into the worker stage only.
FICTION! Some termite nymphs will molt into workers, some will molt into soldiers, and others will molt into reproductives.

Fact or Fiction? As with ants, the termite reproductive caste contains a queen only; males die after mating.
FICTION! The reproductive caste always includes a king (male) and a queen (female). The king mates with the queen for life. This is very different from ant colonies. Ant queens mate when young and store sperm in a specialized organ called a spermatheca to fertilize eggs for several years until their death. Males die relatively quickly after mating.

Fact or Fiction? Mature subterranean termite colonies may contain supplementary reproductives.
FACT! Mature termite colonies may contain supplementary (also called secondary reproductives). They only mature into primary reproductives upon the death of a king or queen, or when the primary reproductives are separated from the colony. There may be more than a single supplementary within a colony.

Fact or Fiction? Termites are related to cockroaches.
FACT! In a study published in 2014, biologists used genetic analysis of 48 termite species around the world. They found that cockroaches and termites shared a common ancestor and diverged about 170 million years ago. Read more here.

Fact or Fiction? Drywood termites are found in North Carolina.
FACT! Drywood termite infestations occur in structures along NC coast. Drywood termites may also be brought into NC in infested furniture brought here from other states such as Florida, California, and New Mexico.

Fact or Fiction? Both the adult and larval stage of wood-destroying beetles feed on wood.
FICTION! Adult wood-boring beetles do not feed in wood. The larvae tunnel through wood as they feed, producing the characteristic sawdust-like frass in galleries. After pupating in the wood, new adults leave exit holes when they emerge from wood.

Fact or Fiction? Carpenter bees not only nest in wood, but also feed on wood.
FICTION! Carpenter bees only nest in wood; they do not eat wood. Carpenter bees actually feed on pollen and nectar.

Fact or Fiction? There is no danger of being stung by grabbing a carpenter bee that has a white marking between its eyes.
FACT! Male carpenter bees have a distinct white marking between their eyes, and because all male bees and wasps lack a stinger, there’s no danger of being stung. Females, however, DO have stingers and are capable of stinging!

What Wood Termites Prefer

Subterranean termite worker (Patty McKeithan Alder, NCSU)

Each year, termites cause an estimated $40 billion in damage globally and damage more than 600,000 homes in the U.S. alone. The amount of wood a single termite colony can damage depends on the species of termite, the type and condition of wood present, and what has been done (if anything) to treat the wood.

Scientists with the U.S. Department of Agriculture (USDA) recently investigated the preference of Formosan termites to 10 different species of wood. Agricultural Research Service (ARS) research entomologists Mary L. Cornelius and Weste L. Osbrink knew the heartwood of some trees contains allelochemicals, which can act as repellents and toxicants to insects including termites. The question was whether boards of lumber contain enough of these chemicals to have a real impact against termites.

Cornelius is now with the Invasive Insect Biocontrol and Behavior Laboratory in Beltsville, Maryland, and Osbrink is with the Tick and Biting Fly Research Unit in Kerrville, Texas. This research was part of the ARS Formosan termite research project in New Orleans, which has now been completed.

The researchers fed the termites a diet from one of ten commercial lumbers: redwood, birch, spruce, southern yellow pine, red oak, Brazilian jatoba, Peruvian walnut, Honduran mahogany, teak, and Alaskan yellow cedar.

After six weeks, redwood, Brazilian jatoba, Peruvian walnut, Honduran mahogany, and teak showed some level of natural resistance and led to an average of more than 74% termite mortality. Southern yellow pine and teak were the least palatable to the termites.

Termites that weren't fed at all (the starvation control) had a significantly lower survival rate on a diet of teak, indicating that there is something in the teak that may actively killed the termites.

The study also provided the first evidence that termites will eat, damage, and survive to some extent on Peruvian walnut. While Peruvian walnut caused high termite mortality - only 16.4% of termites survived after feeding on Peruvian walnut for 6 weeks - the wood also sustained a high rate of feeding damage. In the rest of the wood species, termite survivability went hand-in-hand with low consumption rates.

The researchers concluded that their ranking could be a guideline when choosing lumber in areas of high termite infestation. If the specific compounds in the resistant wood are identified, these compounds may eventually offer the possibility of a natural treatment for wood to protect against termites.

Read more about this research in the November issue of AgResearch HERE.

Dr. Mike Waldvogel Receives IPM Award

A big congratulations to Dr. Mike Waldvogel! 

He received the the 2016 Southern Region IPM Center "Friends of IPM – IPM Educator" award. 

This award is given to individuals or groups to recognize successful outreach and education programs that facilitate the implementation of Integrated Pest Management (IPM). Mike was recognized in an award ceremony at the Southeastern Branch ESA meeting in Raleigh, NC on March 15, 2016.

Dr. Waldvogel Mike is an Extension Specialist and Extension Associate Professor with NCSU's Department of Entomology.

Final Rule Will Clarify and Improve the Transparency of Ingredients in Minimum Risk Pesticide Products

The Environmental Protection Agency has published a rule to clarify the substances on the minimum risk pesticide ingredient list and the way ingredients are identified on product labels. Minimum risk pesticides are a special class of pesticides that are not required to be registered with EPA because their ingredients, both active and inert, pose little to no risk to human health or the environment. The Agency is reorganizing these lists and adding specific chemical identifiers to make clearer to manufacturers, the public, and federal, state, and tribal inspectors the specific ingredients that are permitted in minimum risk pesticide products. EPA is also requiring producer contact information and the use of specific common chemical names in lists of ingredients on minimum risk pesticide product labels.

EPA’s revisions to the exemption, announced in a December 28, 2015, Federal Register notice, do not alter the substance of the minimum risk pesticide ingredient lists, but more accurately describe which chemical substances can be used in pesticide products that are exempt from federal pesticide registration requirements. State enforcement agencies have expressed support for the changes.

EPA believes the industry – manufacturers of these products and businesses considering entering the market for minimum risk pesticides – will benefit from clearer guidance. Consumers will benefit from the clearer information on which chemicals the products contain. 

To view the final rule, go to: EPA-HQ-OPP-2010-0305-0047

Managing Bed Bugs in Multifamily Housing

A community-wide bed bug management program was evaluated in a study just published by Richard Cooper, Changlu Wang, and Narinderpal Singh.

A model IPM program for managing bed bugs was implemented in an affordable housing community for elderly and disabled residents in New Jersey. The IPM program included resident and staff education, initial inspection of apartments using Climbup® interceptors, and treatment of infestations. Initial treatments included laundering of bed linens, encasement of mattress and box springs, vacuuming to remove visible bed bugs, and steaming. Pesticide applications during initial treatments were limited to diatomaceous earth and Phantom aerosol.

Follow-up service visits continued every two weeks until no bed bugs were captured in interceptors, seen during inspection, or reported by the residents for three consecutive visits.

At the onset of the study, property management was unaware of 71% of the infestations. These results show that depending on residents to report bed bug infestations is unreliable, which may lead to increased infestation size and further spread of bed bugs to other apartments.

Cooper's experiment is the first research to document the success of a bed bug IPM protocol in an entire apartment complex. Key findings of the study included:

• Reporting of bed bug activity by residents was unreliable. 
• By the end of the 12-month study, a 92% elimination rate of treated infestations was achieved, reducing the community-wide infestation rate from 15 to 2.2%.
• The high level of success achieved in the study required a great deal of persistence and vigilance. An average of seven visits were required in the apartments where bed bugs were eliminated.
• The use of interceptors proved to be valuable tool in the IPM program. Ninety-four percent of the apartments identified through proactive inspections were detected using interceptors. In visual inspections conducted in 286 units where interceptors detected no bugs, only four additional infestations were found.
• Control strategies relied mostly on non-chemical measures. No pesticides were ever applied to beds; instead, mattress and box springs were encased, and visible bed bugs were removed or killed by vacuuming, steaming, or physical removal with forceps. When pesticides were used, applications were mostly targeted to areas bed bug activity was seen. Just three of 66 apartments where bed bug activity was high received treatment of baseboards with liquid residuals. An average of 201 g of finished product was applied to treat 66 apartments, which is >90% less compared with other reported field studies.
• Average labor and chemical costs for the 12-month IPM program for 66 apartments was $456 per apartment, a figure in line with other programs and which the authors believe can be reduced in subsequent years of a contract. Proactive inspections accounted for 54% of the costs, while treatment accounted for 46% of the costs. 

The study’s bed bug IPM program provides a model that is both effective and economically practical for use in affordable housing communities suffering from chronic bed bug infestations.

You can read the publication in its entirety here:  https://www.researchgate.net/publication/271589914_Evaluation_of_a_model_community-wide_bed_bug_management_programin_affordable_housing

Kissing Bugs and Chagas Disease in North Carolina

By now, you’ve probably heard news reports out of Texas and now North Carolina, about a "deadly" insect, the kissing bug. The bug is native to the southern United States, South America, Central America and Mexico, and can carry a parasite Trypanosoma cruzi that causes Chagas disease.

The Eastern blood-sucking conenose (AKA kissing bug),

Triatoma sanguisuga, is native to NC and much of the 

southern and middle U.S.

Kissing bugs tend to bite sleeping people on the thin skin near their eyes or mouths, hence the nickname. Unfortunately, the bugs also defecate at the site of the bite. These feces can enter the wound when a person scratches or rubs their face, and if the bug was infected T. cruzi, infection with Chagas disease can follow.

There are at least two species of kissing bugs that are native to North Carolina: Triatoma sanguisuga and T. lecticularia. But before you panic, it’s important to know that most cases of Chagas disease are actually from rural areas in the New World tropics. Cases of Chagas disease in the United States are rare; most cases of Chagas disease have been diagnosed from people who traveled here from outside the country. In fact, since 1955, only seven verified cases of native-infected Chagas have been reported in in the United States, and none of those occurred in North Carolina. One reason they are not frequently encountered is because kissing bugs are nocturnal and prefer to hide during the day.

There are many other insects in North Carolina that look similar and can be mistaken for kissing bugs. Kissing bugs belong in the family Reduviidae. Other bugs in this family are similar in appearance, but they feed on plants and other insects and can inflict a painful bite when disturbed. However, only kissing bugs are known to transmit the Chagas parasite. Kissing bugs feed on a diversity of wild and domestic animals including wild rodents, other wild mammals, domestic dogs, and humans. You can find some common insects that are mistaken for kissing bugs by visiting the NCSU Plant Disease and Insect Clinic blog.

So, what exactly do kissing bugs look like? Kissing bugs are around one inch in length when fully grown and somewhat flattened. The sides of their abdomen and thorax are striped, alternating black and orange/red. (see photo above). The legs of kissing bugs are thin compared to most assassin bugs. The front of the head is elongate and the mouthpart is long and thin. They also have a prominent spine on the back of the thorax. 

To reduce the chance of kissing bugs entering the home, work on excluding them. Some of the following may help to seal the home to keep the bugs outside:

• Cut back trees and shrubs so they do not touch or overhang the house
• Don’t stack firewood or other items directly against the house
• Install weather stripping around loose fitting doors and windows.
• Seal cracks and gaps in the foundation with caulk
• Close up weep holes with copper mesh
• Use stainless steel mesh wire to block larger access points in the attic
• Make sure window screens aren’t torn or ripped 
• Turn off outside lights at night. If that is not possible, use “bug bulbs” or try LED bulbs that have a wavelength less attractive to insects

If you think you’ve encountered a kissing bug, trap the bug in a container without touching it. Fill the container with rubbing alcohol or freeze the bug. Take the bug to your county cooperative extension center, health department or university lab for proper identification.

Mosquitoes and West Nile Virus

Many of you may have seen the report that someone in NC has died from West Nile Virus (WNV). Although the NC Department of Human and Health Services does not release patient-specific information in these situations, the person was subsequently identified by his family as being a 76 year old man in Durham County.

Only about 1% of people who become infected develop severe illness, and many people may not become sick at all. The symptoms of West Nile Virus can take 3-14 days to present themselves. Therefore, many people may not attribute their illness to the virus until it becomes severe. Among people that develop severe illness (i.e., excluding those individuals who exhibit minimal or no symptoms), the mortality rate ranges from about 3% to 15%, with the rate being highest among the elderly (as likely the case here).

As we've seen in previous years, West Nile Virus occurs far less frequently in people in North Carolina as compared to other nearby states. We did not have a human case of WNV in 2014 and only about three in 2013. Those numbers are not intended to trivialize the fact that people were affected (some fatally). It's just a matter of making sure that people don't panic about the disease and just use common sense. West Nile Virus is far less frequent here than other mosquito-borne diseases, such as Eastern Equine Encephalitis (EEE) and LaCrosse Encephalitis (LACE). EEE is typically more common in eastern NC and occurs most commonly in horses that were not inoculated against the disease.

Birds are the "amplifying hosts" for West Nile virus, which basically means that infected mosquitoes transmit the virus to birds which are in turn bitten by other mosquitoes which acquire the virus and spread it to even more birds. Some mosquitoes species feed primarily on birds but the species that will readily feed on both birds and mammals are the ones that pose the risk of spreading the disease to people. The mosquito species that transmit West Nile Virus tend to breed in waste water collection areas and stagnating catch-basins. You can also find them breeding where water collects after storms and begins to stagnate with an abundance of organic matter present. So, one obvious approach for residents is to make sure that they clear stagnating water sources on their property. It doesn't matter if this water is on a 1000-acre farm or on a 0.1-acre home lot, water that collects and stagnates has the potential to become a mosquito breeding site. Across most of North Carolina, the Asian tiger mosquito remains our most common pest species and it will exploit similar pools of stagnating water on the ground and in man-made objects.

As always, rainfall will dictate a lot of ebbs and flows of mosquito activity but with a multitude of urban water sources as breeding grounds, we will continue to see mosquito activity continuing into the early fall as long as temperatures are favorable (although the shortening day lengths and declining temperatures will send some mosquitoes into diapause). Although pesticides have their use in mosquito management, the first response by individuals should focus on "source reduction" (i.e., disrupting/eliminating those breeding sources rather than worrying first about what to insecticide to spray).

Follow these tips below for a good source reduction program:

• Bird baths - simply flush them out with a garden hose, and the mosquito larvae is flushed out in the process. Plus, the birds will appreciate the fresh water. For horse owners with water troughs near stalls or out in pastures, one option is to use a product such as "Mosquito Dunks," which contain the bacteria Bacillus thuringiensis israelensis, which kills the mosquito larvae (but not the adults). Although you can use them in outdoor water bowls for pets, it is far simpler (and better for your animals) if you "tip and toss" the water from the bowl and replenish it with fresh water daily.

• Old cans, tires, etc. - empty them and get rid of them (legally, don't simply toss them along the highway to become someone else's problem).

• Outdoor flower pots - empty the water from the dishes/trays underneath them. Your plants have plenty of water without the overflow. This also helps reduce fungus gnat problems in the plant soil.

• All of that built-up debris in your gutters that you've been planning to clean out? It's time to actually do it and get rid of the water and decaying material that attract mosquitoes.

• Rain barrels - if you collect water from your gutters or some other system, make sure the barrel is screened to keep out debris and mosquitoes

• Tarps covering boats, grills, firewood, etc. also collect pockets of water that can remain for 1-2 weeks.

• The bed of that '57 Ford pickup that you've been "restoring" for the last 25 years can collect water particularly if the tailgate faces uphill in the yard.

• Kiddie pools - if they're not being used by kids, they're probably being used by the mosquitoes (and maybe some toads). So, empty them. The same thing applies to pools (in ground or above ground) that aren't maintained. In some of our western states where drought has been a major issue, swimming pools have become mosquito magnets (and the swimming pool owners have become the object of attention for emerging female mosquitoes looking for a blood meal).

• Drainage ditches - they're meant to collect storm water runoff temporarily. Keep them free of debris so that water flows and has time to filter into the soil.

• Decorative fish ponds can be a source of mosquitoes if they contain a lot of vegetation that provides hiding places for the mosquito larvae. "Mosquito Dunks" are an option here.

• Tree holes - when limbs fall off trees, the remaining hole in the trunk can collect water. Flush that out or put a small piece of a mosquito dunk into it.

Another critical issue - personal protection. The majority of mosquito-borne disease incidences, whether they're human or equine, are due to a lack of personal protection. Horse owners need to spend the time and money to get their horses vaccinated against EEE. For us two-legged creatures, we simply need to take precautions when we're outdoors for work or recreation. If it's too uncomfortable to wear long-sleeved shirts and long pants, then cover all exposed areas of the skin with an insect repellent (seehttp://insects.ncsu.edu/Urban/repellents.htm). A few other important points about using repellents:

• Do not put repellent on skin that will be covered by clothing.

• Children spend a lot of time outdoors even when school is back in session because the weather has been favorable. The greater the amount of time spent outdoors can increase the likelihood of getting bitten by a mosquito (and potentially a higher likelihood of being bitten by an infected mosquito). Before applying a repellent to a child, read the label carefully to make sure that it contains concentration appropriate for use on children.

• When using repellents on children you should apply the product to your hands and then rub it on their arms, legs, neck, etc. If you allow your child to rub repellent on their arms and legs, they need to wash their hands immediately afterwards because they will inevitably forget and either rub their eyes or stick their fingers in their mouths.

In terms of yard treatments for mosquitoes, the idea is to treat mosquito resting spots on the lawn and surrounding landscaping. These treatments can help reduce mosquito populations and are certainly a choice for individuals to make. With regard to fogging outdoors for mosquitoes (e.g., with the hand-held or backpack fogging machines available at hardware stores), these pieces of equipment produce a fine aerosol mist. So, bear in mind a few things if you decide to go that route:

• Spray when there is little (if any) wind. Otherwise, the chemical simply drifts off your property rapidly and may not kill as many mosquitoes are you expect.

• Remove or cover children's toys, pet water & food bowls, barbecue grills, etc.

• Avoid spraying flowering plants during the day when bees and other pollinators are out there. We're already losing enough honey bees and you don't need to contribute to the toll. 

• Stay upwind of any application that you're doing and take precautions by wearing proper Personal Protective Equipment (PPE) - long-sleeved shirts, long pants, hat, goggles, and preferably some respiratory protection. 

• More importantly, watch out for drift off of your property. The chemical may end up on someone else's property, whether that's private property or a park, school, or some other public property. Your neighbor's may or may not be receptive to the chemical mist and you need to be aware in particular what is going on at the adjoining property so you don't contaminate people/children, pets, food, honey bee hives, etc. 

And along that line, one other very important point - mosquitoes have no concept of property lines. They are simply out there looking for a blood meal whether it's you or your neighbor. Chemicals may knock down mosquito populations right now and provide some "control." However, mosquito management is what is really needed and that requires a proactive community effort in order to succeed. "It takes a village" applies to mosquito management and you only need one "village idiot" to make that program be unsuccessful. Communication and cooperation are as important (or more important) to make mosquito management work.

We have information on mosquito control on the web at
http://insects.ncsu.edu/Urban/mosquito.htm.