Identification of Insect Damaged Wood Termites

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Identification of Insect Damaged Wood Termites Powered By Docstoc
					                                                                                                                               Revision Date: 3/1/1997
                                                                                                                               Dewey M. Caron, Extension

                            Identification of Insect-Damaged Wood

Termites are small, yellowish-white to brown insects that live in large colonies in the soil.

Colonies are made up of many individuals, including a king, queen, workers, and soldiers. The
colony produces swarms in the spring. "Swarmers," which are winged reproductives, suddenly
appear in large numbers, but then quickly disperse. Termites move in mud "shelter tubes" to
get from the soil to wood- or cellulose- containing materials like paper
or cardboard.

Damage. Interconnected, irregular cavities and tunnels are lined or
partly filled with claylike mud material. It appears "messy" with
cemented mud in hollowed-out wood. The tunnels often follow soft
parts of annual rings, producing a wafered appearance. Damage is
most common near ground or foundation or in wood close to or in
contact with the ground. It is usually not evident on unbroken
surfaces. Hollow mud tubes called "shelter tubes" may extend from
the ground to nearby wood surfaces. Termites attack almost any kind
of wood.

     It is the policy of the Delaware Cooperative Extension System that no person shall be subjected to discrimination on the grounds of race, color, sex, disability, age, or national origin.
Old house borer
Old house borers are in the large family of longhorned beetles. Adults are elongate (1/2 to 1
inch long) and black. They have grayish hairs and markings on the thorax, and wing covers

over the abdomen.

The larvae are elongate (about 1 inch when mature) and slightly flattened. They have 3 pairs
of tiny legs behind a hardened head capsule.

Damage. Large oval holes that connect to tunnels that deeply riddle
coniferous sapwood. The tunnels are filled with fine, loose powder that
may fall from holes at the surface, creating cone-shaped sawdust piles.
The holes are usually not numerous and may not be noticed until the
internal tunnels are exposed.

Powder-post beetles

                  Powder-post beetles are actually several types
of beetles. Most common are:

    1. Anobiid beetlea
    2. Bostrichid beetles

    3. Lyctid beetles

Anobiids attack almost any kind of wood, but seem to prefer old wood. Bostrichids prefer to
infest the sapwood of most hardwoods. The sawdust in the tunnels is caked together, rather
than loose and powdery. Lictids infest the sapwood of hardwoods. They prefer newly
seasoned wood, such as lumber in yards, new hardwood floors, and tool
handles. Adults are tiny but typical of beetles. Larvae are grub-like with 3
pairs of tiny legs.

Damage. Powderpost beetles make small round holes at sawed or round-
edge surfaces when they emerge as adults. Holes may be numerous,
especially on sapwood portions. Holes are connected to tunnels filled with
coarse to powdery sawdust. Sawdust may fall from holes if wood is
jarred, or may be pushed out by adults when they emerge. Adults fly to
windows, but they are seldom numerous.

                          Carpenter ants
                          Carpenter ants (Campanotus spp.) are large (1 1/4 to 3/4 inch long)
                          and usually black. The winged forms have large brownish wings with
                          distinctly darker-colored veins. The winged and wingless forms may
                          appear in large numbers inside the binding or as solitary foragers.
                          They usually swarm in the fall.

                          Since there are many kinds of ant, get confirmation that you have
carpenter ants.

Damage. Wood infested by carpenter ants has interconnected irregular
cavities and tunnels. The cavities have clean, smooth walls, without
sawdust. Damage is seldom evident on unbroken surfaces.

Loose, coarse, fibrous sawdust may be piled nearby. Damage can be in
any part of the building, commonly in decayed, moist, or naturally soft
kinds of wood. Carpenter ants are common in woods in the yard, but
uncommon in sound, dry wood in homes and other structures.

Quick Guide
Surface Frass (bore          Galleries                                Re-
                                             Wood Attacked                    Name of Insect
 Holes     dust)             (tunnels)                            infestation
                                          Part and
           Mixture of soil
                          concentric     Sapwood
           and fecal
                          with annual    and
           material, may
                          rings;         heartwood
           be plastered                            Seasoning or             SUBTERRANEAN
None                      surfaces       of                     Yes
           in crevices or                          seasoned                 TERMITES
                          plastered      softwoods
                          with light     and
           tunnels on
                          tan fecal      hardwoods
                          cavities not
           Tiny, hard                    Sapwood
           round-ended                   and
           pellets with 6                heartwood
                          rings;                                            DRYWOOD
None       longitudinal                  of        Seasoned       Yes
                          surfaces                                          TERMITES
           ridges; less                  softwoods
                          clean and
           than 1 mm                     and
                          smooth; no
           long                          hardwoods
           Coarse,                       Sapwood
                                                     Often damp
           sawdust-like,                 and
                          Partly                     and partly
           contains                      heartwood
None or                   concentric                 decayed;               CARPENTER
           insect                        of                      Yes
obscure                   with annual                prefer soft            ANTS
           fragments;                    softwoods
                          rings;                     grained
           below nest                    and
           only                          hardwoods
                          Round, 10-
                          12 mm          Sapwood
Round,     Coarse,
                          diam., 15-     and       Seasoned;
10-12      sawdust-like,                                                    CARPENTER
                          18 cm long,    heartwood soft grained Yes
mm         below surface                                                    BEES
                          primarily      of        unpainted
diameter   openings only
                          with grain     softwoods
                          of wood
Round,     Absent or      Oval, up to    Sapwood                            ROUNDHEADED
                                                     Unseasoned No
5-6 mm     excelsior-like 13 mm long     and                                BORERS

diameter                   diam.          heartwood                         (SAWYERS)
Round,                   Round, up        and
         Coarse, tightly                                                    HORNTAILS
4-5 mm                   to 5 mm          heartwood Unseasoned     No
         packed                                                             (WOODWASPS)
diameter                 diam.            of
         Fine to coarse Round, 1.6-       Sapwood of
         powder;          10 mm           hardwoods Seasoning               BOSTRICHID
2.5 -7
         tightly packed diam.;            primarily;  and newly    Rarely   POWDERPOST
         , tends to stick numerous;       minor in    seasoned              BEETLES
         together         random          softwoods
         Fine powder                      Sapwood of
                          Round, up
Round, with elongate                      soft-woods
                          to 3 mm                                           ANOBIID
1.6 - 3 pellets                           and
                          diam.;                      Seasoned     Yes      POWDERPOST
mm       conspicuous;                     hardwoods
                          numerous;                                         BEETLES
diam.    loosely                          rarely in
         packed                           heartwood
                                          Sapwood of
                           Round, up                  Newly
Round,                                    ring- and
          Fine, flour-     to 1.6 mm                  seasoned              LYCTIC
0.8 - 1.6                                 diffuse-
          like; loose in   diam.;                     with high    Yes      POWDERPOST
mm                                        porous
          tunnels          numerous;                  starch                BEETLES
diam.                                     hardwoods
                           random                     content
                                          Inner bark
            Coarse to fine
                                          and surface
Round,      powder, bark-
                           Round, up      of sapwood Unseasoned
1.6 - 2.5   colored,
                           to 2.5 mm      only; in    logs under   No       BARK BEETLES
mm          tightly packed
                           diam.          softwoods bark only
diam.       in some
                           same diam.     Sapwood
Round,                     as holes on    and
0.5 - 3                    surface;       heartwood                         AMBROSIA
            None                                    logs and   No
mm                         across         of soft-                          BEETLES
diam.                      grain; walls   woods and
                           darkly         hardwoods
          Coarse to        Oval, up to
Oval, 3 - fibrous; some    12 mm long               Unseasoned              ROUNDHEADED
10 mm blunt pellets;       diam.; size              logs and   No           BORERS
                                       of soft-
long      loosely to       varies with              lumber                  (GENERAL)
                                       woods and
          tightly packed   species
Oval, 6 - Very fine        Oval, up to Sapwood      Seasoning to Yes        OLD HOUSE

10 mm    powder and       10 mm long   only of    seasoned        BORER
long.    tiny pellets;    diam.;       softwoods,
         tightly packed   numerous     primarily
         in tunnels       in outer     pine
                          marks on
          Coarse         Flat oval up
Oval, 3 -                             heartwood
          powder some to 10 mm                                    FLATHEADED
13 mm                                 of        Seasoning    No
          blunt pellets; long diam.;                              BORERS
long                                  softwoods
          tightly packed winding


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