SB 
818 
C576 
ENT No. 82. Issued January 2, 1907. 
ited States Department of Agriculture, 
BUREAU OF ENTOMOLOGY, 
L. O. HOWARD, Entomologist and Chief of Bureau. 
PINHOLE INJURY TO GIRDLED CYPRESS IN THE SOUTH ATLANTIC 
AND GULF STATES. 
By A. D. HOPKINS, 
In Charge of Forest Insect Investigations. 
Pursuant to certain complaints of serious injury by wood-boring 
insects to girdled cypress timber in the South Atlantic and Gulf States, 
the Bureau of Entomology began a series of experiments and investiga- 
tions with special trees girdled on definite dates in every month of the 
year, as well as with those girdled in regular operations at known dates 
or periods, to determine whether or not there was any important rela- 
tion between the month or time of year the trees were girdled and sub- 
sequent injuries. 
This work was personally conducted by specialists of the Bureau in 
cooperation with cypress manufacturers in southeastern North Carolina, 
southern South Carolina, southeastern Georgia, western Florida, and 
southern Louisiana. It was begun in the spring of 1903 and continued 
until December, 1904. Over 300 trees were examined, and observations 
were made on practically all of the different species of insects which are 
in any manner associated with injury to the wood and bark of living, 
dying, and felled, as well as girdled, cypress. 
RESULTS OF INVESTIGATIONS. 
The principal injury to the wood of standing girdled cypress was 
found to consist of pinholes in the sapwood and heartwood caused by 
two classes of small wood-boring beetles, called timber beetles, ambrosia 
beetles, pin borers, “pin worms,’’ etc. They bore the so-called pin- 
holes in the wood as places to deposit eggs and rear their broods, and 
the latter, when fully developed, leave the wood and fly to other trees 
to repeat the process. 
One of these classes of wood-boring beetles is represented by small, 
short, cylindrical, reddish beetles one-eighth to one-tenth of an inch in 
length, which are exclusively sapwood borers. As a rule they are not 
common in girdled trees, but are abundant in logs from living trees. 
The other class is represented by elongate, slender, reddish, cylin- 
drical beetles three-eighths of an inch in length, which often extend: 
their borings deep into the heartwood and are often common and quite 
