FIELD COCKROACH IDENTIFICATION
The field cockroach or vaga cockroach is a small cockroach and likely introduced from southwest Asia into the United States. It now inhabits a wide range from Texas to the West Coast and north through California. The field cockroach is common in irrigated regions of southern Arizona and adjacent areas in Southern California. Field cockroaches are very similar in appearance to German cockroaches but can be distinguished by the blackish-brown area on the face from the mouthparts to between the eyes: Field cockroaches have black stripes between their eyes and German cockroaches do not. Field cockroaches are slightly smaller, 9.6-12.8 mm (about ¼ of an inch), and olive-brown in color.
FIELD COCKROACH LIFE STAGES
Field cockroaches go through three developmental stages: eggs, nymphs, and adults. The female completes her first egg case within about eight days. Adult females carry the egg cases (ootheca) until they are ready to hatch. Each egg capsule usually contains between 30 and 40 young. The eggs incubate for 20 days and nymphs complete development in 44-56 days. Development from a newly emerged nymph to adult can be completed in about 3 months. Females may live for more than 200 days, producing between 200 to 300 offspring or 6 generations a year.
FIELD COCKROACH THREATS
Field roaches feed largely on decomposing vegetation, including fruits, such as dates, and occur under stones, clumps of earth, debris, and similar objects. Unlike most other species, field cockroaches are not gregarious and rarely enter buildings. Unlike the German cockroach, the field cockroach can fly, is not repelled by light, and can often be seen during the day. Outdoors, field cockroaches thrive in leaf litter and piles of cut grass. During drier parts of the year, the field cockroach may enter structures in search of moisture. Because field cockroaches so closely resemble German cockroaches, some homeowners will think they have German roaches invading their home, when they are actually field cockroaches. While they are not as widespread as other species, field cockroaches cause similar concerns. Field roaches hide in cracks, crevices, and corners of homes. They can also spread bacteria if they gain access to kitchens and pantries. Populations of this fast-breeding cockroach can increase rapidly if left unchecked.
FIELD COCKROACH EXTERMINATION AND CONTROL
The most effective ways to avoid a field roach infestation is through proper sanitation, exclusion, and removal of hiding places. The following prevention tips can help to reduce the occurrence of field cockroaches and other invasive insects:
- Field cockroaches hide under the firewood, leaf litter, and debris. Store firewood away from the home and clean up leaf litter and plant materials outdoors.
- Trim shrubbery around buildings to increase light and air circulation, especially near vents, and eliminate ivy or other dense ground covers near the house, as these may harbor cockroaches.
- From around the outside of buildings remove trash and stored items such as stacks of lumber that provide hiding places for cockroaches.
- Consider keeping a layer of gravel about 6 to 12 inches wide around the perimeter of buildings.
- Store food in insect-proof containers such as glass jars or resealable plastic containers.
- Keep garbage and trash in containers with tight-fitting lids and use liners.
- Keep trash cans away from doorways. Remove trash, newspapers, magazines, piles of paper bags, rags, boxes, and other items that provide hiding places and harborage.
- Eliminate plumbing leaks and correct other sources of free moisture. Increase ventilation where condensation is a problem.
- Vacuum cracks and crevices to remove food and debris. Be sure surfaces, where food or beverages have been spilled, are cleaned up immediately.
If you have tried all the above measures and still experience field cockroach issues, It is best to consult a licensed pest control operator for interior pesticide treatments.