The Republican journal., 1883-08-02
The Dying Hackmatacks.

The Boston Sunday Herald publishes
an interview with Prof C. V. Riley of the
I. S. chronological Commission in the
course of which the following was said
regarding the investigation of Dr. Pack
ard of the cause of the destruction of
spruce trees which has attracted so much
attention.
"What have you to say Of the injury to
the hackmatack 2"
A good deal has been said of the dying
Of these spruce trees during the past
two or three years, a number of different
theories being held. SO | requested Dr.
A. S. Packard who is one of the special
agents of the chronological division, and
is preparing for the department special
report on forest tree insects, to give par
tlcular attention to the subject. have
just left him at Brunswick, and, after
thorough examination, we are of one
mind on the subject, and indeed there is
no reason for theory" The injury is
entirely due to the work of a false cater
pillar or saw fly larva-a worm about
three tourths Of an inch long when full
grown, with a black head, a pale green
body, with darker green side stripes and
ten pairs Of prolegs. The insect may be
known as the spruce saw fly. 1t passes
the winter in tough brownish cocoon in
the moss and turf on the surface Of the
ground. The parent fly is black, with
some four of the abdominal segments
reddish yellow. 1t issues from the CO.
coon in June, and the female lays her
eggs in the terminal young shoots, max :
ing about dozen missions in each, and
thus causing the shoot to curl in a
characteristic manner. A few eggs may
even now be found unmatched, but the
bulk of them hatch in June, and by the
present time OF year most of the worms
have left the trees and spun up.
"But have not other explanations been
offered to this injury? 2"
"Oh, yes Where facts and close
observation are wanting, theories abound.
The chief of these are change of climate
and odd age Some, high in authority,
have adopted this last but there is no
| sense in H. Trees die of old age grad
ually and individually. This kind OF
decay is easily recognizable in any
species, and in forest is not particularly
perceptlble because younger trees grad
ually take the place of the failing ones
Your hackmatacks of all ages are being
killed by the worm, which, while partial
| to old trees, spares neither youth mol
age. Occasionally tree dies from some
other cause, as by borers. for instance, OF
injury by fire; but such trees are con
| spicious from their brown dead leaves
| which are not eaten off,"
| ''What is the extent OF the injury,
professor:"
1T extends throughout New England
and into New York, and Dr. Packard,
who has had good opportunities of get
ting at the facts, thinks that about two
! thirds OF the trees throughout this whole
extent are already destroyed"
"Have you any remedy to recon-
mend ?"
Man is impotent to stem such wide
| spread injury. Trees can be saved. but
the element of cost vii! disarm all at
tempts on large scale Smaller trees
could be easily protected 10y spraying
them with water impregnated with az
senic in some one OF the now well known
forms, as, for instance, one pound Of
London purple to 50 or 100 gallons OF
water, or one pound of Paris green to #
gallons of water. \ certain quantity o.
flour should be stirred in to give greater
adhesiveness. These liquids sprayed or
to the trees will kill all the worms that
hatch. | shall publish in the Forthcoming
annual report of the department an ac-
count OF some improved methods of ap
plying them to trees by means of 1
special spraying nozzle attached to {
rubber tube which is passed through z
long bamboo rod and connected with {
force pump in a barrel or tank drawn by
horses. A large number of trees can bt
poisoned III d comparatively short time
and with minimum quantity of material
II | had grove of Young spruces
should certainly adopt this method 0
saving them. 1t occurs to me that some
thing may be done also in the way o
raking up old leaves and moss on thu
ground on which the cocoons are formed
and burning them during the fall of the
year. However, these methods are only
valuable in limited areas, and We shall
doubtless have to await natures owl
remedy, namely, the increase of tht
insects natural enemies, or some me
THEOLOGICAL influence that may injuriously
affect it. Whenever species becomes
SO prodigiously abundant as this has be
come corresponding scarcity and i'm
munity from it is very apt to follow
swiftly. Whether this change will Occur
before all the trees are killed or not, it il
impossible to say"
"You have no idea of the value of the
trees destroyed Z"
II have not any statistics of the damag,
in New England, but it is very great anc
Important
"Does not the injury extend to othe
evergreen trees ?"
"No, notice good deal Of injury anC
OF dying twigs and branches among tn.
white pines, the tips, Or whole branches
and sometimes small trees being brown
and dead. But this has no connection
with insect work, nor does it result from
the effects of fire. | have examined i
closely, and have come to the conclusion
that it results from the exceptiona
drouth that has prevailed for the last
three years combined with the severt'
OF the past winter. The ground go
dried out to an unusual depth, and whel
the roots OF coniferous tree once dr.
they perish -