Carpenter Ants
Carpenter ants are a nuisance by their presence when located in parts of the home such as the kitchen, washroom, parlor and other quarters. When 20 or more large winged and/or wingless ants are found indoors, in the day near one location, it is possible that the colony is well established in the house and the nest may have been extended into sound wood, now and again causing structural damage. They do not eat wood, but often remove quantities of it to expand their nest size. Although, if only 1 to 2 large wingless ants are erratically crawling, they might simply be foraging for food with the nest located outside. Outdoors, they are frequently seen running over plants and tree trunks or living in moist, partly rotten timber stumps. Even so, carpenter ant inquiries rank first over all other household/structural pests in Ohio.
Identification
Carpenter ants are among the biggest ants found in homes and reside in colonies containing three castes comprising of winged and wingless queens, winged males and different sized workers. Winged males are much smaller than winged queens. Wingless queens measure 5/8 inch, winged queens 3/4 inch to the tips of their folded brownish wings, small minor workers 1/4 inch and large major workers 1/2 inch. Workers have some brown on them while queens are black. Workers have large heads and a small thorax while adult swarmers have a smaller head and large thorax. Carpenter ants have a smoothly rounded arched (convex) shape to the peak of the thorax when looked at from the side and a pedicel between the thorax and abdomen comprising of only one segment or node. They have constricted waists, elbowed antennas and the reproductive's forewings are larger than the hindwings, transparent or brownish and not easily removed. Adults are commonly black with some species red, brown or yellow occurring on body parts and legs. Eggs are about 1/8-inch long, cream colored and oval. Larvae are legless and grub-like, later pupating in tough silken, tan-colored cocoons erroneously stated as "ant eggs."
Life Cycle and Habits
Queen Worker
Winged female and male carpenter ants (swarmers) emerge from mature colonies usually from March to July. After mating, males die and newly fertilized females (mated for life), generate a new colony in a tiny cavity in timber, under bark, etc. and each lays 15 to 20 eggs in 15 days. The egg stage takes about 24 days, larval stage 21 days and pupal stage 21 days or about 66 days from egg to adult at 70 to 90 degrees F. Cool weather may lengthen this period up to 10 months. The colony does not produce swarmers until about three years later. A mature colony, after three to six years, has 2,000 to 4,000 individuals. During the first breed, larvae are fed entirely by a fluid secreted from the queen's mouth where she does not take food, but uses stored fat reserves and wing muscles for her nourishment. The few workers emerging from the first hatch assume duties of the colony, collecting food, excavating galleries to enlarge the nest and tending the eggs, larvae and pupae of the second generation. Workers regurgitate food for nourishment of the developing larvae and queen. She has few duties except to lay eggs.
In later generations, workers of several sizes are produced (polymorphism) into major and minor workers, that are all sterile women. Males formed are winged swarmers. Larger "major" workers guard the nest, battle intruders, explore and forage for food while smaller "minor" workers expand the nest and care for the young. workers, when disturbed, bring off the larvae and pupa, which should be fed and tended or they die. In a mature colony, there is typically one queen with 200 to 400 winged individuals produced as swarmers. Workers have strong jaws and readily bite (sharp pinch) when contacted.
Nests are normally established in soft, moist (not wet), decayed wood or from time-to-time in a current wood cavity or void area in a structure that is perfectly dry. Workers cut galleries in the wood, expanding the nest size for the enlarging colony. Galleries are occasional, usually excavated with the wood grain ( sometimes across the cereal) into softer portions of the wood. The walls of the nest are smooth and clean (sandpapered appearance) with shredded sawdust-like timber fragments, like chewed up toothpicks (frass), carried from the nest and deposited outside. These piles of timber fragments, often discovered beneath special openings (windows) or nest openings, may contain portions of insects, empty seed coats, etc.
Carpenter ants do not eat timber but excavate timber galleries to rear their young ants and carry aphids to plants, placing them on leaves for the output of honey dew. The food diet is of great variety (omnivorous) of both plant and animal origin such as plant juices, fresh fruits, insects (living or dead), meats, syrup, honey, jelly, sugar, grease, fat, honey dew (aphid excrement), etc. They feed readily on termites and usually never live with them in a home. Workers are known to forage for food in as much as 100 yards from their nest.
Control Measures
The most important and often most hard part of carpenter ant control is locating the nest or nests. As soon as the nest location is discovered, control is very simple and simple. Now and again more than one colony is present in the structure or on its grounds, so a thorough inspection is extremely important. Steps to a productive inspection include an interview with members of the family, inspection indoors, inspection outside and sound detection.
Interview
Often children and adults of the residence know where ants are seen, where huge numbers are most prevalent, movement patterns, moisture in the structure, moisture problems of earlier times, if swarmers were seen, location of sawdust-like material in piles, populations outdoors, etc.
Inspection Indoors
Nests can be located in either moist or dry wood. Yet, carpenter ants prefer to nest in moist wood with a moisture content considerable over 15 percent, often a consequence of rain, leaks, condensation, etc. Structural wood is about 12 to 15 percent moisture. A moisture meter can find wet places to pinpoint possible nest locations. Inspect behind restroom tiles, around tubs, showers, sinks, dishwashers, washing machines, refrigerator drip pans, etc. Check timber affected by moisture from contact with the soil such as steps, porch supports, siding, seepage from plugged drain gutters, chimney flashing, wooden shingle roofs, hollow porch posts, columns, leaking window and door frames, window boxes, crawl spaces, pipes, poor pitch of porch roofs, flat deck porch roofs, under porches, attics, etc. Often times, nests are found in dry environments, like hollow veneer doors, curtain rods, small void areas between the door casing and ceiling, false beams, or under insulating material in attics. Search for damaged timbers, swarmers in spider webs, wood piles indoors, piles of timber debris removed from the colony (pencil sharpener shaving-like), "windows" or small opening to a nest, etc. Gently tap floor joists, etc. with a hammer. A nest cavity gives a hollow ring. A knife blade will penetrate the wood if infested.
Baiting
Some may make use of tiny piles of sugar at two to three feet intervals around the kitchen, washroom, etc. in attempt to determine where the nest can be found. Others use drops of honey or corn syrup placed on the rear of masking tape. Make observations late in the evening, following ants back to their nest entrance.
Flushing Agent
A household aerosol spray, containing pyrethrins and piperonyl butoxide, applied directly into cracks, crevices or holes, will excite the ants (repellent action) causing them to come running out revealing the presence of their nest in a few instances.
Inspection Outdoors
Look for ants traveling from a tree or stump to the structure. They may travel over tree branches or vines touching the roof, electrical and telephone wires, fences beside the house, piles of firewood, logs, or railroad ties nearby or hollow living trees with entrance knot holes, etc. Workers are most active in the evening (midnight), traveling from their nest to a food source following trails but no particular trail leading directly to the nest. They do establish chemical (pheromone) trails.
Sound Detection
An engaged colony may produce a different, dry rustling sound ( often times loud), much in-line with the crinkling of cellophane. It can be heard in a wall when standing in a room. A listening device, such as a stethoscope, may be helpful when weather conditions are quiet and outside noises are at a minimum. Even a cat may hear noises in the home caused by ant mandibles (jaws) not from chewing timber or eating food, but as their form of conversation, particularly when the colony is disturbed.
Prevention
Homeowners should trim all trees and bushes so branches do not touch or touch the house. Correct moisture problems such as leaking roofs, leaking chimney flashing, or plumbing, poorly airy attics or crawl spaces and blocked gutters. Replace rotted or water-damaged timber and eliminate wood to soil contact. Remove dead stumps within 50 feet of the house, if practical, and repair trees with damage at broken limbs, and holes in the trunk. Seal fractures and crevices in the foundation, especially where utility pipes and wiring occur from outside. Be certain to store firewood off the land far from the house and bring in just enough firewood (first examining it) to be utilized quickly . Consider non-organic mulches near the house in heavily infested ant areas. High moisture conditions must be eradicated to help control carpenter ants, prevent future attacks and stop " timber decay" fungus infection.
This magazine comprises pesticide suggestions that are subject to change whenever. These recommendations are given only as a guide. It is always the pesticide applicator's responsibility, legally, to read and follow all current label directions for the specific pesticide being used. As a result of constantly changing labels and product registration, some of the testimonials given in this writing may no longer be legal by the time you read them. If any facts in these recommendations disagrees with the label, the recommendation must be dismissed. No endorsement is meant for products mentioned, nor is criticism meant for products not mentioned. The author, The Ohio State University and Ohio State University Extension assume no liability resulting from the application of these recommendations.