3-8.
COCKROACH SURVEYS
a. Cockroaches have become well adapted to Iiving with man. Most species
prefer warm, moist situations such as cracks and crevices near heated equipment (for
example, stoves, steam tables, water heaters, dish washers, and so forth.). A favorite
b. Cockroaches are nocturnal and are usually seen when you enter a room and
turn on the light. If cockroaches are seen during the day, there is usually a heavy
infestation. One good way to survey a buiIding for cockroaches is by use of an aerosol
such as a pyrethrum or pyrethroid insecticide. Cockroaches may be flushed out by
spraying the insecticide directly into suspected hiding places. Cockroaches react
quickly to this type of material and, if they are present, they wiII be seen scurrying
about. One should not apply aerosol formulations of insecticide to electrical outlets or
connections. Another excellent survey technique is the night time survey of a
buiIding/room with the Iights turned off. Cockroaches do not see yellow or red Iight, so
a lens of one of these colors can be placed on your flashlight to search for cockroaches
when they are most active.
c. The presence of egg cases is a sure indication of cockroach infestation,
except in the case of the German cockroach. In most species, the female cockroach
attaches her egg case to objects such as boxes, walls, curtains, pipes, and so forth.
These egg cases are readiIy identifiable; they resemble a small pouch or purse. The
egg case of some species even appears to have a zipper along the top edge.
Figure 3-9 shows some of the different types of egg cases. The female German
cockroach, on the other hand, does not deposit her egg case but carries it attached to
her body untiI the eggs are ready to hatch (see figure 3-10). The finding of cockroach
feces is another sure indication of infestation. Cockroach droppings are usually rod-
shaped, almost black in color, and from 2 to 4 mm in length. Droppings of some of the
smaller species may be smaller and wiII appear to be grains of black sand.
d. Roach traps may be used in estimating populations. The trap may be
constructed as shown in figure 3-11. The traps are baited with fruit such as bananas or
apples, or with greasy food such as bacon grease or peanut butter. Placement of the
trap is important to the success of trapping. Place it in the corner, touching walls,
equipment, table legs, and cabinets. Roaches may also be collected this way and
tested to determine cockroach resistance to insecticides.
e. Commercial type roach traps are available as standard issue items. These
very effective traps are equipped with a strong adhesive to capture roaches drawn or
attracted by a buiIt in chemical attractant. Placement of these traps is the same
described in paragraph d above.
MD0170
3-16