Archive for the ‘Pest Questions’ Category

Aug 2, 2012 – Food or Wood – It Really Matters

QUESTION:

I have a sample of what looks like drugstore beetles a customer is seeing in the kitchen of their house. They had them identified by another source that said they were Anobiids. They indeed did have Anobiid in the substructure that we have treated for. My concern is these sample beetles are not Anobiid and they have a drugstore beetle problem also. As the two beetles are very similar, what can I look for to distinguish one from the other?

ANSWER:

Ah yes, the importance of that accurate ID. Is it eating the woodor eating their food, and obviously knowing which one it is matters greatlywhen it comes to control. Drugstore and Cigarette beetles are common stored food pests and they are in the family Anobiidae. Also in this beetle family are Deathwatch and Furniture beetles, and there may be some superficial resemblance. However, drugstore beetles are pretty darned distinct. They are dark brown, slightly hairy and with an overall dull (not shiny) caste, and their antennae consist of several short segments at the base followed by 3 much larger, much longer segments that compose the outer 2/3 of the antenna. As with most Anobiids the prothorax (the first section of the thorax) hangs over the head when viewed from above. 

You can go onto PestWeb’s Pest ID resource and compare some pictures. Look in the Pests / Pest ID which goes to the program and then use the search field for specific bugs. The wood infesting Anobiids that are most common along the Pacific Coast seem to be the Furniture Beetle. This is similar in general appearance to the Drugstore but it is gray rather than brown, a bit larger, and the prothorax is not as smooth in profile, but has an enlarged bump on top. You can see images of this in our Pest ID as well. The Anobiids that infest wood prefer relatively damp wood, so your locality in Washington should provide that for them, as does the climate in San Francisco where I have seen major issues with this beetle. Anything that can be done to lower the relative moisture level in the wood will help with the control and prevention. 

But, in your case, it has to begin with the ID to determine just what this is. There are plenty of native species of Anobiids out there too that may come to lights at night, but if you are finding them in numbers inside the home it suggests a source inside as well. Since these are in the kitchen, were I a betting man I’d go with Drugstore, and that doesn’t necessarily make it all easy. This beetle has a very wide range of foods that it will infest, so essentially anything that was a plant and now is dry food could be infested. I even once saw a kitchen cutting board absolutely filled with the beetles that were feeding on impregnated greases and oils in the wood, so they do have strong enough jaws to penetrate some hard surfaces. 

I suggest examining the samples with good magnification and compare them with our images on PestWeb. 

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Pest QuestionsAugust 02, 2012

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Jul 30, 2012 – Whitefly Management

QUESTION:

I would like to know the best way to control whiteflies.

ANSWER:

Believe it or not, identification of the kind of whitefly may be of some value. We have had invasions of some exotic species, such as the Ash Whitefly, that were successfully combated by the release of parasitic wasps, a program conducted by the state department of Agriculture. There are many parasitic and predatory insects that feed on whiteflies that may be able to keep their numbers under control, so it pays to at least evaluate the problem to see if it is taking care of itself. 

Whiteflies are difficult to eradicate. The early stage is called the larva stage and it usually is sessile, remaining attached to the plant and feeding through this early stage. While in the larval stage it covers itself with a layer of wax and the wax repels water-based sprays, often keeping the spray from contacting the actual insect. In addition, the larva usually attach to the undersides of leaves, making it much more difficult to spray a plant or tree thoroughly enough to contact the larvae. They also have a high potential for breeding large numbers very quickly, so missing any of them leads to rapid re-infestation. The adults look like tiny white moths, but in reality these insects are more closely related to scale insects and mealybugs in the “Homoptera” (now Hemiptera). The adults sometimes can be so numerous on shrubs that just walking past the shrub or brushing against it could result in a cloud of the insects flying around and getting inhaled. 
Yellow sticky traps placed near infested plants will attract a lot of the flying adults, and at the least will reduce their numbers a bit. This is unlikely to eradicate them and they will be replaced by new adults fairly quickly, but it does give relief. If you are able to spray the undersides of the leaves thoroughly you can have good results uses a horticultural oil such as Safe-T-Side or neem oil or even an insecticidal soap. These will not provide any lasting protection but can kill the larva present at the time. Another possibility is the use of a systemic like imidacloprid (Merit 75 WP) that can be applied to the soil below the infested plant. This could not be used on food plants like tomatoes but it is labeled for whiteflies on “trees, shrubs, flowers”, so generally for many other landscape plants. If applied to the soil it may take a week or more to move up into the foliage where it then is ingested by the feeding larvae. If applied as a spray to the foliage it may affect them more quickly but not last as long. 
Monitoring the success can be complicated by the fact that the larvae and their waxy covers may persist on the plants long after they are dead, so monitoring for the presence of new adults is more reliable than expecting the infested leaves to suddenly be free and clear of the early stages. 

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Pest QuestionsAugust 01, 2012

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Jul 31, 2012 – A Pattern Not So Unique

QUESTION:

What type of spider has an hourglass shape on its back? I have tried to look up information on the internet and it either says it’s the black widow, which I know has the hourglass on the belly, but other information that pops up is The Redback Spider. Is this the spider that we are seeing? I have had people tell me they have them in the Fayetteville, NC area and we have seen them in the Salisbury, NC area. I would like to know what this is exactly. Many customers only know the hourglass and if they see it on the back they call in a panic about the widow spider. I want to make sure I am knowledgable for my customers as well as myself. How are we able to control these spiders as well. Is there a website that I can get more information from?

ANSWER:

This is the problem with customers having just a little bit of knowledge on a topic. First, black widows are so common in California that I suspect nearly every home has a few of them hanging around, and I have been into warehouses (empty, fortunately) where a PMP killed hundreds of them. Frankly, while I will not live with widow spiders in close company their presence does not send me screaming from the home. Our phobia here in California is the Violin Spider which, interestingly enough, does NOT LIVE in California. I guess we most worry about the things that do not exist. 

First, the Redback Spider is a black widow species – Latrodectus hasseltii – in Australia, and as far as I know it has never been found in the U.S. But, the female is the same shiny black of our widow spiders and the difference is that red marking on the dorsal side of the abdomen instead of underneath. The basic description of an “hourglass” marking from your customers probably reflects the basic knowledge they have of spiders, knowing that the widow spiders have this hourglass shape and thus they refer to that shape anytime they see something that resembles it. In fact, there are a lot of very different spiders that have patterns on top of their abdomen or thorax that could be described as kind of like an hourglass, including many of the ground spiders, some jumping spiders, wolf and crab spiders, and probably even some of the Orb Weaver spiders if the person seeing it is not familiar with these different kinds. 
There also now is the Brown Widow spider – Latrodectus geometricus – that is common in Florida and becoming widespread in California. It is a mottled gray-brown instead of shiny black but otherwise has the same basic body shape and long legs of the black widows, and a reddish-orange hourglass on the ventral side of the abdomen. Perhaps your customers are even seeing their spiders from the underside, but mistaking it for the top. 
There are so many different kinds of spiders that making a guess as to the ID of yours could easily be wrong and lead you astray. Better would be to take some examples to your local department of agriculture or university entomology museum and get a positive ID. That will enable you to get specific information on the proper spider and to be able to reassure your customers that the only really dangerous spiders in North America are the widow spiders. Even the Brown Recluse hazard is terribly overblown, although its bite can be serious to sensitive people. 

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Pest QuestionsJuly 31, 2012

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Jul 28, 2012 – Going Crazy In Florida And Texas

QUESTION:

The ground is moving with Caribbean crazy ants. I have never seen anything like this. After identifying, monitoring and scouting I need control action guidelines. Do you have any suggestions on what to do next?

ANSWER:

Thisinvading ant species has proven to be a challenge, in part because of theoverwhelming numbers that it provides to us. It is given the scientific name ofNylanderia pubens, and is similar to other “crazy” ants we have in the U.S. with its single node, long antennae, and extremely rapid movements. It isnative to islands in the West Indies, but has been in southern Florida since at least1953. A more recent invader appeared in the Houston area of Texas around 2002,and is dubbed the Rasberry Crazy Ant, and this species is also giving humansfits with it massive numbers and highly active behavior. The exactidentification of the Rasberry Crazy Ant is still not determined, but it is aclose relative of the Caribbean Crazy Ant if not the same species. Currentresearch suggests that the Caribbean and Rasberry Crazy Ants are the samespecies, but slightly different geographic races.

Theproblem is not any immunity the ants have to current insecticides, but insteadis the sheer numbers that they occur in. They so overwhelm an area that eventhough millions may die there are millions more to take their place. One PMPreports he commonly finds them inside oak trees that have hollow interiors fromrot, and treating within this void causes major numbers of the ants to emergequickly, but hours later they are still emerging. The pesticides easily killthe ants on contact, but there are too many ants to affect them quickly. So farthe Rasberry Ant is still confined to southeastern Texas and the Caribbeanspecies still confined to the south half of Florida, but living things have away of expanding their range. Not a lot is known about their specific biology,but it appears they have colonies with multiple queens, increasing theirpotential to replace lost workers. They nest in almost any available place,feed on both proteins and carbohydrates, and forage in wide trails of thousandsof workers.

TheUniversity of Florida continues to work on developing an effective controlstrategy for this ant, as Texas A&M is also doing with the Rasberry Crazy Antin their state, but some of the standard IPM practices can be offered to atleast reduce the problems in landscapes and homes. Trimming vegetation awayfrom the exterior walls of structures reduces pathways into the home, creatingbare strips around the immediate perimeter of the foundation helps keep theants further away and maximizes the efficiency of any pesticides applied, andremoval of unnecessary clutter on the soil reduces nesting sites. Keepinglandscape plants free of pests such as aphids or scale insects reduces thehoneydew that these ants crave.

Atthis time even the university suggests that pesticides are necessary, althoughnot the perfect answer. In some feedback from PMPs in south Florida there issome promise using synthetic pyrethroids for their repellent action, and pyrethroidsof most kinds have given some relief from the ants for several weeks. The useof these as a perimeter treatment around structures may provide a “buffer zone”that lasts for a month or longer. There also has been good kill of the antsusing the non-repellents such as Termidor or I Maxx Pro, although completeelimination of nests and colonies does not seem to be happening yet. Baitinghas met with limited success so far, even though the ants do seem to feed oncarbohydrate baits. One suggestion that was offered was the use of the newerproduct Transport GHP, which received great label expansion in early 2008, withgood uses now for ant control around the exterior of structures. This isanother of the non-repellents and may be worth giving a try. The newerTransport Mikron has also given some PMP’s good results on these ants, alongwith the use of Talstar granules where labeled.

Themost up-to-date information from Texas A&M and from University of Floridatell us that the magic wand for this ant still does not exist. They suggest theuse of contact insecticides sprayed as a perimeter application aroundstructures and along trails the ants are using. This can be followed byplacement of sugar baits that are replaced regularly to keep them fresh andacceptable. Removal of all potential harborage sites on a property will help tolimit the presence of the ants, and this will be anything on the soil,including piles of landscape debris, boxes, lumber, etc. 

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Pest QuestionsJuly 30, 2012

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Jul 29, 2012 – Bugs And The Weather

QUESTION:

How does humidity affect ants?

ANSWER:

This is an interesting question and one that I initially felt I would only be able to speculate on. But, thanks to my copy of the extraordinary book by E.O. Wilson and Holldobler – “The Ants” – I actually found some authoritative information. It may boil down to the fact that every species of animal has the “ideal” circumstances for their activity periods – foraging, nest building, etc. Those adapted to any particular habitat are going to do best at a certain range of temperatures and moisture conditions. Honeybees may not emerge for food gathering until temperatures reach a certain minimum and may halt their outside activity when the temperature reaches a certain maximum acceptable for them. 

Likewise, ants react to temperature and humidity, and in particular the exposed workers outside of the nest. A colony in the soil can somewhat moderate their own living conditions by maintaining the temperature and humidity levels by clustering together or moving deeper in the soil. But, if the ideal conditions do not exist above soil level or within the first few inches of the surface the colony may forego swarming flights or workers may not emerge to forage. For ant species that have evolved in a desert environment, such as red harvester ants, the ideal humidity may be much lower than that of the Red Imported Fire Ant, which evolved in tropical rainforests. Ants evolved to live in the Upper Midwest or in Canada would prefer outside conditions to be at temperatures lower than ants native to Florida or Arizona, so a heat wave in Wisconsin could cause the ants to hole up in their colony until things return to the ideal state. 
This can be said of many other insects as well – they are affected in some way by the weather. A particularly mild and dry winter is going to cause some insects to have population surges in the spring and others to not do as well. It often depends on what their food sources are, and a warm and rainy early spring could lead to more vegetation early in the year and thus more plant-feeding bugs to take advantage of this. This in turn might lead to more predatory insects that now have a greater food supply of the plant feeding bugs. 
Ants may be at the top of the list when it comes to the affect of weather, as they all are social insects and thus work as a group for the benefit of the entire colony. When something outside the colony, such as the weather, is not conducive to their success they will withdraw and wait for things to return to normal. 

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Pest QuestionsJuly 29, 2012

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Jul 26, 2012 – Bed Bugs And Hotels

QUESTION:

Can you treat bed bugs by fumigation or fogging hotel guest rooms? What is the best treatment?


ANSWER:

I will say first that “fogging” is going to be fairly ineffective for resolving a bed bug problem. Fogging the air with pyrethrum may be able to kill some exposed adult bugs, but it will have no effect on bugs that are hidden within the many, many hiding places they are likely to be. This includes seams of mattresses, within dressers and all the crevices on dressers, behind head boards and items hanging on the walls, along the seams of carpets at the wall junction and behind wall baseboards, and even inside TV’s or bedside clocks. All of the bugs hiding within these places need to be killed or extracted in some other way, so don’t waste time and product fogging the air. 

Dealing with The Common Bed Bug – Cimex lectularius – is now known to be a very difficult and complex process. In a hotel it is an even larger challenge because of the ability of these bugs to move from room to room and floor to floor. I encourage anyone who plans to become involved in bed bug control to attend every training event possible and to read every resource available on them. This is an evolving process and new technologies are coming along each year. One of these is advancements in monitoring devices, such as the new “Verifi” detectors from FMC. These incorporate new attractants that seem to greatly enhance the performance, better enabling you to determine if the bugs are present in a room. There still are pitfall traps and other monitors that also effectively capture bed bugs, and these should be part of any program. 
Fumigation using Vikane is an option, but not a great one for a hotel due to the size of the building. The entire structure would have to be enclosed in a sealed tarp for the fumigant to be used effectively. If this hotel has a runaway problem on multiple floors and many rooms then fumigation might be an appropriate choice. Properly done you can guarantee that immediately after the fumigation all bugs and their eggs will be dead and the property free and clear of the problem……..for awhile at least. But, the cost would be very high, so it has to be compared with the cost of treating rooms one at a time, repeating treatments in most cases, and waiting for weeks to months to be certain the problem is gone. The cost of a fumigation also needs to be balanced with the liability aspect for the hotel, which may be losing business because of the infestation or be unable to rent many rooms because they are under treatment. A fumigation could quickly put all those rooms back into service. 
So, the “best” treatment for bed bugs is going to have to depend on the situation. If it is just one or two rooms then these MUST be taken out of service and treated very carefully and thoroughly using a combination of dusts within voids, residual contact products within cracks and crevices, installation of mattress encasements, and vacuuming. Many companies now also routinely use heating of individual rooms with good success, but this takes training and a lot of equipment. While any rooms are being treated all surrounding rooms, above, below, and to the sides, must be inspected and monitored to ensure they are not infested as well. 
Hotels, by now, had BETTER have a bed bug policy and protocol in place for all hotel employees. All of the housekeeping staff must be made aware of what to check for after each guest leaves a room. They also need to be taught how to prevent taking home bed bugs on their own clothing or in their own belongings. The hotel that still turns a blind eye to this problem is going to suffer some serious consequences. 

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Pest QuestionsJuly 28, 2012

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Jul 27, 2012 – Mound, Thatch, or Field – Same Ant

QUESTION:

I have a problem with black mound ants at a school in Central NY. Could you please let me know the best choice of product and application methods? I have heard that you are to dig up the mound and place granules and mix it up few times and apply more granules. This is the first time I have dealt with mound ants.


ANSWER:

Mound ants are also referring to as Thatch, Thatching, or just Field ants, and most of them are in the genus Formica. They are large ants superficially similar to carpenter ants but with a distinct dip in the top of the thorax, whereas carpenter ants  have a thorax that is evenly rounded over the top. Thatch ants cannot sting, but they can bite, and once they create a little bite wound may spritz some formic acid onto that point to cause a stinging sensation. They almost always confine their activities to the outdoors and natural foods, in particular honeydew. These ants are well aware of where that honeydew comes from and they fiercely protect aphids from other insects that might eat or parasitize the aphids. Doing so they also keep away other pesky insects that feed on honeydew, such as yellow jackets and other wasps and ants. 

They turn the soil to create their colony, and in so doing create the large above-ground mounds that we notice. These may continue to be there and to enlarge for years, and if someone were to inadvertently stand on the mound he would immediately be attacked by the biting ants. A mound nest on a school property could become a liability for the school, so eliminating this nest is appropriate. Otherwise, since they so rarely enter structures the ants can normally just be left alone as beneficial parts of the local environment. 
Treating the mound itself is the correct treatment, generally using either a dust or a spray of contact insecticide and disturbing the surface pretty thoroughly so that you treat the whole mound and into it somewhat. A shovel or rake can be used to turn the surface over as the treatment is being done, taking care not to allow the ants to get up beneath your pants and onto your legs. You might rig up plastic bags as “leggings” around the bottom of your pants and even around the handle of whatever you use to mess with the mound to prevent the ants from climbing onto your hands. 
Keep in mind the state regulations on pesticide use on school properties, and be sure to stay within them. This likely means advance notice of this “emergency” treatment to many parents and posting the site prior to and following the treatment. Since you are not using the pesticide, in this situation, within any kind of enclosed station you would need to follow the regulations in place. 

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Pest QuestionsJuly 27, 2012

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Jul 24, 2012 – Getting To The Source

QUESTION:

The local entomologist ID’d a sample as the carpet or hide beetle that has infested the fireplace area of our client’s home. Inspecting both under and in/over the fireplace we are unable to locate a nesting area that would support this pest. The 4′ crawl space was inspected twice. A chimney sweep took care of the upper works. I would like to hear any eradication ideas and recommended pesticides and application methods.

ANSWER:

I guess we can assume that the ID was accurate, although there can be a big difference between typical “carpet” beetles and hide beetles, with respect to the things they eat. Both kinds are in the family Dermestidae, but hide beetles are more often associated with carcasses and the final bits of skin, flesh, and hair left on the carcass once the flies and other initial insects are through with it. Typical carpet beetles feed on the hair or feathers of carcasses as well as on any grain-based food materials, so old rodent baits, bags of baking goods, dry pet foods are all susceptible to infestation from these smaller, oval beetles. Carpet beetles also feed on dead insects and their assorted remains, so old bee hives or wasp nests often have carpet beetles in them feeding on leftover pupa and shed exoskeletons. Bird nests with leftover feathers or dead chicks could also be a food source for them. 

Which leads us to the question of what might exist in or around this fireplace that could be offering either of these bugs the food they look for. Depending on what kind of fireplace and chimney are here there could be little voids or alcoves up inside that a chimney sweep’s work might not touch, although with their spinning brushes a thorough job ought to dislodge old wasp nests or bird nests. Perhaps you can seal off the opening at the bottom of the fireplace and place some glue traps on either side of that cover, such as plastic sheeting. This may enable you to determine, from captured beetles, which side of the opening the bugs are coming from. The fireplace certainly is not needed in Nevada this time of year, so sealing it shut for awhile shouldn’t be any heartache for the customer and it might help you to narrow the search. If all the beetles you find are on glue traps within the fireplace it could suggest that the problem must be somewhere up inside the chimney. 
If the captured beetles are on the living area side of the fireplace then a continued search for the source is needed, and you might concentrate on looking for grain-based foods rather than animal fibers, although never rule out anything. The adult beetles, in particular, are very active, and may be found wandering well away from their origin as the larvae. I myself had an ongoing problem with them that we finally traced to cupboards in the laundry room where we kept dog “biscuits”, and one of the large biscuits had fallen behind things for most of a year and supported a large population of the carpet beetles. But, there could be wool blankets in storage, wool carpets nearby, wool tapestries on the wall, and other unusual sources near that area. I have also seen ongoing carpet beetle problems due to old rodent baits tossed in the attic and left there. You might investigate this possibility and ask the customer if they have done any rodent baiting themselves. 
There are pheromone traps for carpet beetles and these can be placed here and there throughout the home, the attic, and even the crawl space. Inspecting the glue pads later may offer some clues as to where the beetles are most common and possibly coming from. I hate the idea of using only insecticides to resolve the problem if the source has not yet been found and dealt with. If you have a hidden source it will continue to pump out the adult beetles and continue to attract more of them to the area, since this is the role of these beetles – recycling leftover plant and animal materials. Contact insecticides are great for the mop-up operation to kill any wandering adults and larvae, and any of the pyrethroids should be excellent for this. 
If you determine that somewhere up inside the chimney is the source this is a tough problem. Obviously accessing the exact source is impossible. You may be able to snake a camera up inside the chimney to take a look around, but rigging that up could be interesting. Perhaps another visit from the chimney sweep with more exact instructions on what to try to remove would help. 

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Pest QuestionsJuly 26, 2012

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Jul 25, 2012 – Nasties In Nursing Homes

QUESTION:

What is a good product to use for pest control for spiders, cockroaches, ants, etc. in nursing homes where patients are present?

ANSWER:

A huge consideration here is the physical condition of the people in these kinds of facilities. They likely are going to be older people with serious medical issues, and exposing them or potentially exposing them to toxins is not a good thing to do. There are many insecticide products labeled for use in “Hospitals and Health Care Facilities” and you can review our listing of these on PestWeb in our Product Documents resource, selecting the tab Products by Approved Site / Structures / Commercial Structures. Many or all of these would be effective on these kinds of diverse pests that you mention, but the concern is whether or not they should be applied when the patients are actually present in the room. I suggest that you would be much better off avoiding this, and if a specific room did need to be treated with a “spray” application of any kind the patients in that room should be moved out during the application and until any spray has dried. 

It is likely that the majority of the products labeled for nursing homes are going to mandate this anyhow, and if we pick a single example – Alpine Pressurized Insecticide – the Label states clearly “Do not apply this product in hospital patient rooms or nursing home patient rooms while occupied by the patient”. Even if the Label does not mandate evacuating the room first you probably should have this policy in place yourself to lower your liability. For cockroaches and ants, if treating within the rooms themselves is necessary, you might consider sticking to bait products and non-chemical techniques. Bait gels do not normally require people to be removed from the room as there is no chance of airborne exposure to the active ingredient. Non-chemical techniques include removal of obvious food resources that are attracting these pests to the rooms, vacuuming for removal, and sealing all crevices that serve as entry or harborage points. 
Spider control within any room should be done with a vacuum, as the presence of spiders is going to be only one here and there and easily taken care of with the vacuum. Then, take the fight for the spiders OUTSIDE where they are coming from, and this should be the case for ants as well. Applications of insecticides around the perimeter of the structure are not going to impact anyone on the inside, and if you can intercept them outside before they get in, then all the better. The use of one of the excellent non-repellent insecticides that gives a good transfer effect should be great for eliminating local ant colonies. Do take the time to inspect the exterior carefully, and note in writing where you find contributing conditions that are encouraging these pests to be there. This may be dense vegetation that covers the soil, excessively wet soils, piles of debris that are unnecessary, or plants whose branches touch the structure, etc. Changing the look of the exterior to discourage the pests from being there close to the structure will be very helpful in keeping them outside. 

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Pest QuestionsJuly 25, 2012

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Jul 23, 2012 – Bees and Trees

QUESTION:

What is the best way to control wood boring bees? I have a client who has them and they are killing her tree.

ANSWER:

I am a little skeptical that the bees are the cause of a tree suffering badly. The only real wood “boring” bees will be carpenter bees, and these guys tend to restrict their burrowing to dead wood. It is possible that this tree does have some dead branches or perhaps a dead area on the trunk that the female carpenter bee has discovered, and she now is creating tunnels in it to raise her young. But, except for perhaps some minor digging where the dead wood of the tree might meet some live tissue it should be restricted to already dead wood. 

Leaf cutting bees are much smaller kinds of bees, some about the size of honeybees and others half that size, that often find existing holes in wood or stucco or other outside materials and the female takes over that existing hole as a convenient place to create her tubes of leaf pieces in which she then deposits and egg and some food for her offspring. If the hole is not quite large enough and the wood is soft she may enlarge it slightly, but again this is almost always going to be in an existing hole at the surface. These and some other kinds of small bees will get into the dead canes of roses and other narrow branches with a soft interior and do much the same thing – clean it out enough to create a small chamber for their offspring. But, in general they do not damage the plant. 
Hopefully I am correct on this and that the bees you are seeing are a red herring, with some other actual cause of the tree’s problems. It would be important to get a positive and accurate ID of these bees so that you then will be able to determine what their biology is and their relation with that tree. If they are having nothing to do with it other than nesting in existing cavities then you would then have to analyze the problem more to determine the actual cause. 

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Pest QuestionsJuly 23, 2012

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