Custom Search
|
|
|
||
 are made of a rather hard material called carton, which resembles a dried sponge. Unlike the native
species, carton can be placed in the wall cavity of a building adjacent to the damaged wood. Carton
is composed of chewed wood, soil, saliva and fecal material.
Formosan termites multiply quickly and can cause serious damage in less time than the native
species. If found, treatment within a few months is suggested. The control measures given for the
native subterranean species also apply to the Formosan termites.
4.3.2 Drywood Termites. Drywood termites occur in warm, humid climates. They util-
ize the moisture within the wood they eat. They do not need a source of water to live in wood,
hence, the name, "drywood termite". Several species range throughout the very southern United
States from the east to west coast (Figure 4-11). In southern California and Arizona, southern
Florida, the Pacific area and the Caribbean, new houses may be infected within five years of their
construction. These insects may colonize and damage smaller wooden articles such as furniture and
packing materials, therefore, they can be important pests in wood items returning from the tropics.
Drywood termites tend to work just under the surface of the wood, leaving a very thin veneer-like
layer. Wood damaged by drywood termites has broad pockets or chambers connected by tunnels
which cut across the grain without regard for earlywood or latewood (Figure 4-18). The galleries are
perfectly smooth and have no surface deposits. Some fecal pellets may be stored in portions of the
galleries; the galleries are closed off by partitions made of fecal pellets stuck together with a secre-
tion.
Piles of fecal pellets are usually the first signs of a drywood termite infestation. The pellets are
hard, elongate, less than 1/25 inch in length, with rounded ends, six flattened or concavely
depressed sides and light gray to very dark brown in color. The shape results from the water extrac-
tion process which occurs in the rectum of the termite. The pellets are eliminated from the galleries
in the wood through round kick holes. The holes are closed with a secretion and pellets when not
being used. Probing wood with a sharp instrument or pounding the surface may reveal hidden
damage.
Drywood termites are slightly larger than the subterranean termites, but are similar in appearance.
Swarmers vary in size from 1/2 to 5/8 inch in total length, and are lighter in color than the subter-
ranean species. Drywood termites swarm at different times of the year depending on the geographic
location. The wing veins are the most distinctive feature of the swarmers. There are several distinct
longitudinal veins with many cross-veins in the front edge of the wing. This differs from the subter-
ranean termite wing, which basically has only two prominent longitudinal veins at the front edge.
Drywood termite soldiers are similar to the subterranean ones. However, the soldier of the West In-
dian drywood species has a distinctive black head almost as long as high, and it is concave and
rough in front. The mandibles are not enlarged. The soldiers function only to block openings in gal-
leries with their heads.
4-28
|
 
|
|
|
||
