Oxford Democrat. [volume] (Paris, Me.) 1833-1933, 1919-07-29
The Pine Wesvn.
A GREAT MENACE TO MAINE FORESTS.

A GREAT MENACE TO MAINE FORESTS.
During the past few years several diff
ferent entomologists, each specialist Of
note In his own chosen field, have been
associated with the Maine Agricultural
Experiment Station during the summer
mouths for the purpose of working up
certain groups Of economic insects.
This season Doctor NJ. w. Blackman,
Forest Entomologist, New York State
College of Forestry ct Syracuse, 10 with
US, IN cooperation with the State De-
paftment Of Forestry, studying Maine
conditions with reference to insect forest
pests. Following is his account of one
of the greatest menaces to the pine for
ests OF Maine. A later letter will discuss
its control.
The white pine is the most valuable
and popular Of our native forest trees,
not only on account of Its majestic beauty
bat also because of the rapidity of it's
growth and Its great timber value. In
the past 1t has been the tree most often
chosen In making plantations where
moderately quick return on the invest
ment was desired. Yet because of two
very serious enemies-the pine blister
rust and the pine weevil-the wisdom of
making plantations of this beautiful and
desirable tree 10 this region of the coun-
try is open to very serious question. At
the present time more frequent mention
of the former of these two pests is heard
by those interested in the preservation of
our forests than of the pine weevil. This
is due largely to q we'll organized propa-
ganda based upon real menace to the
white pine and its Kindred species, and
should in no degree be discouraged or
hampered. At the same time 1t is doubt
ful il the blister rust is as important an
enemy to the production Of white pine
timber as is the pine weevil.
The distribution of the white pine
weevil in the state is identical with that
of its favorlte host. Everywhere the
pine occurs in plantations or in open
stands this destructive insect is to be
found, and its work of destruction is not
confined to the white pine but 1t also
attacks several species of spruce and oc-
casionslly pitch pine and jack pine. 1t
is often especially injurious to Norway
spruce and to a less extent to red spruce
when these occur in plantations or in
open stands.
The white pine weevil is an insect ma
tive to this country. The adult is q
small brown beetle about one-f0urth of
an inch long with grey or white mark
ings but differs from the ordinary beetles
in the possession of snout comprising
about one fourth of it's body length.
These beetles lay their eggs in the previ-
Gus years. growth of the terminal shoots
Of the tree during the early spring in
A pril or May. The eggs are placed in
small excavations made through the bark |
Of the pine leader by the mouth parts of
the female. They hatch in s or 10 days
giving rise to small yellowish white
grubs which Immediately begin to feed
upon the inner living portion |
Of the bark. As they grow, these Larvae
work downward eating the entire inner |
bark as they proceed and as they become |
larger destroy ing more and more of the
living sapwood. Just before they COM
plsts their full growth Qate in June or
early in July) the grubs burrow into the
wood near the lower end of the terminal
and there construct small oval chambers |
covered with a deposit Of chewed up |
PARTICLES Of wood known as "chip CO.
,oons." In these cocooIs the Larvae |
transform into pupa and later these give |
rise 10 new generation of adults which |
emerge during July and later. These
ast over the winter and attack new lead
ers the following season. The effect OF
the activities of the larv@ In the living |
leader of the pine Is not at once appar- |
ant, but In few weeks-usually by the
middle of Juue-the new growth begins
TO wilt and very soon dies and the needles
turn brown. The terminal dies back to
The next W horl of limbs below the point |
Of attack or even farther to the second
W horl below. The killing OF the leader
throws the vitality of the tree into the
next lateral shoots below the injury and
these contend for leadership, resulting in
he production of tree with forked or
branched top known by woodsmen as a
'sstag- horn pine" This usually entirely
DESTROYS the commercial value of the
tree and at the same time ruins its sym
metry and beauty. Very often the new
leaders are in turn attacked, which re-
suits in the production of stunted,
bushy growth of no commercial or es-
hetic value. Hundreds of instances have
been observed where this has been car
ried 90 far that from 25 to 100 leaders
were striving for supremacy.
The pine weevil rarely attacks the lead
ers of pines or spruces less than feet or
more than 20 feet high. 1t does not usu-
ally deposit its eggs in weakened sickly
trees but shows decided preference for
leaders which have made more than the
average amount of growth the previous
wear. As has already been intimated,
he insect most commonly attacks trees
growing in the open or in open erowths
and especially white pine and Norway
spruce in plantations. Tho same species
when growing under cover in native
wood lots are often nearly or entirely
exempt from ipjury.-Chas. d. WOODS,
Director.