The evening times. [volume] (Washington, D.C.) 1895-1902, 1897-06-05
INSECT TREE DEsTROYERs
Entomologists Inquiring into the
RavageS of Bugs.
THE PESTS MULTIPLYING
Injuries TO Chestnut and Pine Trees
in the Vicinity of Washington.
Oak, Cedar and Sassafras Succumb-
ing TO the Boring Process of Bee
ties and Other Influences.

The division of entomology of the Depart
ment OF Agriculture has prepared an ar
ticle on insect injury to chestnut and pine
trees in Maryland, Virginia and neighbor-
ing States, which is of considerable inter
est, in view of the extensive destruction
of the pine and spruce forests in the United
States, particularly in that portion which
is southeast of the Blue Ridge range, and
10 a smaller extent Of chestnut Trees in the
same and in other regions.
This injury has been very generally at
trihuted to insects, and there is evidence
that certain wood and bark boring species
have largely contributed to the work of
destruction. The death OF the chestnutS
las been laid 1 he accO unit of the buprestid,
while the death Of the coniferous Tree has
in like manner been accredited to the
scolytid bark beetle.
r. H. Chittenden, who is the author Of
the article mentioned, states that he has
always felt a certain degree of skepticism
as to whether perfectly healthy forest
growth would, save in exceptional cases,
SuCcumb to insect attack, and were not
this view shared toy others it might sound
like heresy to say that the insects mention
ed are perhaps not the original cause of
the Jury. There is more than a suspicion
that a predisposing agency has been at
work IN causing a weakened condition Of
ba tigahaF gf tha vppiOn
Whatever has brought this about, there
is every appca rance tn At the insects in ques-
ton have multiplied in such numbers that
they were fenced 10 attack living, il not
healthy, plants or perish. as they belong to
groups that DO not develop in timber that
mas been dead long enough for the bark
To become separated from the wood.
Such enfeebled condition might be caused
10y bacterial OF fungous disease; or it might
he due toa variety Of other elements, among
which might be numbered too close growth,
defective drainage, insufficiency or super
abundance of subterranean moisture, too
great dryness, or, again, it might he pro-
dGCed lay dry spell, suddenly followed toy
an unUsuaHy wet one, Oh vice versa. IN
the present case il seems that the soil had
undergone some change that has interfered
with the growth OF the trees, or that 4
combination OF unfaVorahle atmospheric
and soil conditions has accomplished the
supposed pTedisp0sing debility. The with
eung and dying of leaves, induced by a
spell of hot, dry weather, following cool,
might he provocative Of tins debility. Pos
sibly ''pine-blight, or what is known as
winter desSica.icn, might explain the orig
nal injury 10 this class of trees.
A peculiar feature OF what ma Y be called
the primary insect injury is that it is due
very largely to native species not pre-
yiOusly known to be injurious The report
maintains that las usual in so many sim
liar instances, these cases of forest-trec
injuries are not brought to the attention of
entOmolOgists until too late for thorough
investigation or experiment"
Iu1SSi Mr.. W II FaTle ywrot e tina tCheSt-
nut trees n Botetout county, Va , were suf
fering from the attacks Of neighbonng in
seUts. The following year MI. Gardiner G.
Hubbard senta pieceUf the bark of chestnut
from his suburban residence near Washing
ton, from which the Department Of Agri-
culture reared in the following spring
specimens OF Agrilus bilineatus In June,
1898, Mr.. j. a. WeddeTburn, of Wash
iugton, who owns property i'll Virginia.
reported serious injuries from insects to
trees, particularly to pine and chestnut
trees Several visits were made by ento-
biological experts to the regions infected,
but In spite OF every effort on the part Of
the Department Of Agriculture, no addi-
tional facts of value were learned.
The department hoped that the full LIE,
economy Of the chief depredatoT, which
proved to be the buprestid beetle, might
be traced, as well as the causes which led
up to the attacks, but this hope was not
realized
Very recently, the Department of Ag-
riCulture learned that insect depreda tors
have attacked cedar and sasSafraS, and
the report has come from northern Illinois
that oak trees there have been similarly
attacked IT is also said that some of the
timber In Michigan is affected