16 Spring 2013 Applegater Notes from a Rogue entomologist in the house and the curious case of the velvety tree BY richard j. hilton “What should I do if I have ants in looking for food or possibly water. These (possibly poisonous) or they the house?” This is a question that every smaller ants can be a number of different can deliver a painful sting. In entomologist has probably heard more and they are referred to by various the case of the velvet ant, it than once. E.O. Wilson, our most famous names, such as sugar ants and piss ants. I is most definitely the latter, living entomologist and a specialist on and folks who have made ants, provides this answer: “Be sure you the mistake of picking one have some time available, get a magnifying When an up or accidentally stepping glass and prepare to study an alien society.” on one while barefoot can While this is not the answer most people is brightly attest to the wasp’s “cow are looking for, it is very typical of E.O. colored like that killer” nickname, as the Wilson, who is an authority on biodiversity sting is reported to be quite and actively involved in preserving it. it usually means memorable. Velvet ants do When I read Wilson’s autobiography, that they taste not live in colonies and are The Naturalist, I discovered that he had usually found crawling on spent some of his youth in Washington, bad (possibly the ground in open areas. DC, and he would often visit Rock Creek poisonous) or When I first arrived in Park where he surveyed and cataloged southern Oregon a little over species of ants there. I grew up in DC and they can deliver 25 years ago, the velvety tree also spent considerable time in the park, a painful sting. ant was not considered to be but I was more likely to step on an ant than a pest. Now it is has become study it. I remember one occasion when, a common ant pest found along with a couple of friends (I am not in the home, particularly if taking sole responsibility for this), I put a was curious about the origin of the term you live in a wooded area. red ant and a black ant together in a jar to “piss ant”; apparently, it is derived from I looked at some references see them duke it out. Having rather short “pismire,” the Middle English word for from the 1990s on ant pests, attention spans, when nothing happened ant, which referred to the pungent smell and the velvety tree ant does after five minutes or so we released the ants of ant nests in the woods. The smell is the not usually warrant even and moved on to other entertainment. In result of formic acid (in Latin, formica), a mention. I also checked Top photo: Carpenter ants are the largest ants found locally. Photo: pestid.msu.edu. Bottom photo: Odorous house ants looking back on my youth, I do think it which was first isolated from ants. Our the Pacific Northwest Insect often invade kitchens. Photo: nathistoc.bio.uci.edu. is fortunate that video games were not most common sugar or piss ant is the aptly Management Handbook, available and that we had only three TV named odorous house ant. These small which is updated annually. In 2007 the their favored nesting sites. Velvety tree channels. But let’s move on before I start black ants are frequent home invaders velvety tree ant is mentioned as a structural ants, as the name suggests, are most often sounding like Clint Eastwood in the movie and give off an odor when crushed. The pest; prior to that the only ants discussed nesting in a tree hole. While you might Gran Torino. odor has been described as the smell of a were carpenter ants. A list of nuisance think it would be simple to track the ants It is very likely that those black and coconut, which I do not get at all, but my ants found in the home does not include back to their nest, I have rarely found it red ants that we captured were carpenter sense of smell is not the best. However, if the velvety tree ant until 2009. So what to be easy. ants. The largest ants that we encounter you happen to crush a velvety tree ant, I happened between 25 years ago and now to Carpenter ants were invading our locally are carpenter ants ranging from one- guarantee that you will get to experience elevate the velvety tree ant to common-pest house a while ago and I tried using a quarter to one-half inch in size and, as their the pungent, acrid smell of formic acid. status? Perhaps it increased its range, but I stethoscope for locating their nest in name implies, they will, on occasion, enter Velvety tree ants are variable in size but have not found much evidence of that. In the wall; this is actually a recommended houses and excavate wood, particularly if may grow to a quarter inch—larger than fact, when I looked into Louis Gentner’s technique, but it did not work for me. the wood has been softened by moisture. most of the pest ants in your house, but old insect collection here at the research On another occasion, we had some Carpenter ants do not feed on wood as do still smaller than a . The color center, I found half a dozen specimens odorous house ants that were getting into termites; they are only removing the wood of the velvety tree ant varies from a dark of occidentale, or velvety tree the kitchen and I happened to be digging to create a nesting space. brown head and abdomen to a red or even ant, collected here locally dating back to around the foundation for another reason Then there are those small ants yellow thorax, and “velvety” refers to a layer the 1930s. when I unearthed their nest. I did feel that are often seen invading the kitchen of fine hairs on their body. Could something have changed in the a slight pang as I saw the worker ants Velvety tree home environment to favor the velvety tree scurrying for shelter, most of them carrying ants are not to be ant? Well, it just happens that the velvety a small white larva in their mandibles. But, confused with the tree ant has a distinct proclivity for nesting with the nest demolished, the ants were no velvet ant (this is in Styrofoam insulation. They seem to love longer a problem in the house. the problem with the stuff. I guess it makes sense—why mess If you have ant problems, it common names). around with damp wood when it is so is recommended to block points of The velvet ant is easy to chew a nice cavity into Styrofoam? entry. Remove plants right around the actually a type Carpenter ants will occasionally nest in foundation, especially tree limbs that are of solitary wasp; attic insulation, but they do not seem to touching the roof since ants will often the females are prefer it the way the velvety tree ants do. climb on vegetation to access your house. wingless so they I have seen velvety tree ant nests in walls, Baiting can be an efficient way to eliminate resemble ants. ceilings, even doors and windowsills that ants in the house. The ants will take the They are large, contained foam insulation. My hypothesis poison bait back to the nest and feed it to very hairy, and is that the proliferation of foam insulation the developing larvae, thereby eliminating have patches of over the last 25 years in our homes has the nest. When using ant bait, try to bright red. When provided a new and most favorable habitat check and see that the ants are taking the an insect is brightly for velvety tree ants to exploit. bait. Ants will often be looking for either colored like that But remember, both velvety tree ants sugar or protein and, if the bait is not The velvety tree ant has become a common house pest, it usually means and carpenter ants are using the structure what they are looking for, they may pass particularly in wooded areas. Photo: bugguide.net. that they taste bad only as a nesting spot. Although they may it up. While ants are a wonderful object feed on foodstuffs from indoors, their of study, I realize that most people do not food is primarily obtained outdoors; they want to share their living space with an eat mainly live and dead along alien society. with honeydew (i.e., sugary excretions) Richard J. Hilton produced by other insects such as aphids. 541-772-5165 If ants are taking up residence in your Senior Research Assistant/Entomologist home, finding and eliminating the original Oregon State University nest will usually provide excellent control. Southern Oregon Research Carpenter ants found in the home are often and Extension Center coming from a nearby tree stump, one of [email protected] HAPPY ST. PATRICK’S DAY!