CA BRANCH 3 Structural Pest Control
Exam/195 Questions and Solutions
How can you tell the difference between wood suffering from brown rot and
wood suffering from white rot? - -Wood infested with brown rot typically:
• appears dark brown,
• shows excessive shrinkage,
• develops cross-grain cracking, and
• can be crushed easily to form a brownish powder.
Wood infested with white rot on the other hand, often:
• appears whiter than normal,
• shows normal shrinkage,
• does not crack across the grain,
• is spongy to the touch.
-What is the difference between the stains caused by stain (sapstain) fungi
vs. mold fungi? - -Sapstain fungi live on the starch in wood cells. These fungi
may discolor the sapwood entirely or in patches. This stain is deep within the
wood and cannot be removed by brushing or planing.
On the other hand, discoloration caused by mold fungi is superficial. This
means that you can usually remove the discoloration by brushing or planing.
However, on hardwoods with open pores (very large and visible vessels) such
as the oaks, the surface molds may cause stains that are too deep to remove
easily.
, -How can you distinguish between winged termites and winged ants? - -
Look at their antennae, waists, and wings. Winged termites have straight
antennae, thick waists, and wings that are equal in size and shape. Winged
ants have bent antennae, narrow waists, and forewings that are larger than
the hind wings.
-Name the four basic castes of termites. Describe the basic function(s) of
each caste. - -Workers - gather food, maintain the galleries, tend the young,
and groom the other termites.
Soldiers - guard the colony against predators.
Primary reproductives - "swarmers" that fly out of their colonies to start new
colonies of their own. They are the future kinds and queens of new colonies.
Secondary reproductives - supplement egg production in the presence of the
king and queen and can take over the egg laying if the queen dies or begins
to fail.
-Do subterranean termites live entirely within wood? Why or why not? - -No,
because they require a constant source of moisture to survive. However,
they can live in wood with less than 20% moisture by getting their moisture
from the ground. They transport this moisture through flattened, earthen
shelter tubes that serve as passageways from the soil to the infested wood.
-How do subterranean termites most often infest wood in buildings? - -They
gain entry through untreated wood that touches or is close to the ground,
particularly at porches, steps, and terraces. They can also infest buildings
through cracks or voids in foundations or concrete floors that make it easy
for termites to reach wood that is not close to the soil.
-Describe the frass pellets of drywood termites. - -They are small and
cylindrical with six depressions on the sides. These pellets are unique to
drywood termites and are used for identification.
-Where do drywood termites most often occur? - -In southern Florida,
southern California, and along the southern gulf coast of the United States.
-Do drywood termites live entirely within wood? Why or why not? - -Yes,
because they require little moisture (wood MCs as low as 5%). Unlike
subterranean termites, drywood termites have no connection with the soil.
-List several ways you can protect wood from termites. - -To protect wood
from subterranean termites, you can:
, • apply insecticides to the soil around buildings, and
• avoid using wood mulches next to buildings.
To protect wood from subterranean and drywood termites, you can:
• use physical barriers on foundations, and
• use properly preserved wood, which makes it undesirable as a food source.
-Describe the frass of powderpost beetles. - -Powderpost beetle frass
appears as a fine wood dust or powder. Slight jarring of infested wood can
cause the frass to sift from holes. This is a sure sign of a powderpost beetle
infestation. In addition, the frass of anobiid beetles has a distinctive hotdog
bun shape.
-For most wood-boring beetles, what life stage causes the most damage to
wood by boring inside the wood? - -The larvae (grub). The exception is the
ambrosia beetle in which the adult bores within the wood.
-How do ambrosia beetles damage wood? - -They degrade wood by staining
it, by creating numerous entrance holes (pinholes), and by boring inside the
wood.
-What type of wood does each group of wood boring beetles discussed in
this manual prefer? - -Ambrosia beetles - green logs or green lumber;
softwoods and hardwoods.
Powderpost beetles - seasoned lumber and timbers, particularly joists, sub
flooring, hardwood flooring, sill plates, and interior trim; softwoods and
hardwoods.
Old house borers - seasoned wood; softwoods such as pine, spruce, and fir.
Flatheaded borers - living trees as well as recently felled and dead standing
softwood trees; rustic structures and some manufactured products.