Daily Kennebec journal. [microfilm reel] (Augusta, Me.) 1870-1975, 1896-09-29
The Extending Range Of Tent caterpiuars.

ING GAtenuln8 mango Of uenl CaIefpuiaIS.
The following information Is taken
from bulletin SO, N. H. experiment sta
ton:
The ordinary food-plants of the tent
caterp1llars are the apple and the vari-
Gus Kinds OF wild cherry. The moths
apparently choose these in preference
to all other trees for the reception of
the eSg-masses. Blu during the out
breaks or the insect in New England
the last lew years,as in fact in previous
outbreaks IN other regions, many of
the aterplliar nave been forced by
munger 10 attack the foliag of other
trees ana SHRUBS. In many localities
the leaves OF the apple and cherry trees
upon which the insects fed when first
Matched, nave been wholly devoured
before the caterpillarS were half grown.
Or course this must be the result when
more are laid upon a tree
or shrub tina can be matured upon its
leaves. Thus threatened by starvation
the caterpillars have been forced tn
leave their nests, descend to the yro,pd
n crawl about in search of food
Many of them ascend the nearest trees
and shrubs, n nibble at their leaves
Ii these leaves are not too distastefnI
the caterpillars are likely to remain ,na
complete their growth upon the no,
food-plant thus found. If the insects
are unable to live upon the leaves tba,.
are likely again to crawl away in o,,as,
of something better. Doubtless thou-
sands of them perish outright in this
| search for food. while myriads of others
~ N a I'm rn11- aInprA fN
either die before maturing into moths
or develop into feeble adults.
But it is very probable that many of
these caterpillars which are able to
complete their larval growth upon new
food plants will survive all vicissitudes
and mature into moths that apparent
ly are likely to deposit eggs upon the
| variety of tree that has furnished them
food. In this way the insect will be
likely soon greatly to extend the limits
of its food-supply. n become much
more difficult to subdue than it now is.
The ease is suggestive of the famous
Gypsy Moth that has lately been caus-
ing UGH alarm in Massachusetts. The
unusual righteousness of this pest arises
from the ability of the c~aterpilars to
feed unOnleaves of all sorts-hard wood
trees, evergreens, shrubs. and herba-
ceous plants. Therein lies its menace:
and if the tent caterpillar is permitted
to continue establishing itself upon
new food plants, u descendants may
have a somewhat similar pest to con-
tcnd with.
That this is not an imaginary danger
can be seen from Fig. s. and from
other photographs which we took but
have not reproduced in this bulletin.
showing the work of the tent cater
pillar upon trees and shrubs not on its
usual bill of fare. And the most sug-
SestiVe fact in connection with these
changes of God is to be found in the
sreat dissimilarity of the other food
plants, h apple and cherry belong
10 the great rose family of plants: bo-
tanically speaking they are related to
each other as we'll rs to the rose. the
peach, the pear, the plum. the noun
tain ash, and others. 1t is we'll known
that insects have family preferences in
the matter of food: that if a given in
sect feeds upon a given plant we need
not be surprised to find it also upon
another plant closely related, belong
ing to the same family.
III view Vi tilS We sflplih expect the |
tent caterpillar when it was forced to
increase its range of food to attack the |
peach, cultivated cherry. rose, and
other plants of this family. This has
been done, and each of these is now on
the tent caterpillar's food list, but We
have also found it feeding freely and
apparently thriving upon such widely
separated plants-so far as botanical
kinship is c-oncerned-as the oaks Gig. |
s. the hickories. the birches. (see |
photograph on title page,) the bar |
berry, and the willows and poplars. II
found a large tent W upon The low
evergreen known as the juniper. but the
caterpillars from it evidently fed upon
4 neighboring barberry.
During the latter part of the cater
pillar season one can frequently find
dead and dying c~aterpillars Upon the
outside OF the tent, stretched at full
length. Some of these will be simply
sluggish, others evidently nearly dead.
others dead and rupturing at a touch.
letting escape the liquid decomposed |
body contents. Some will be hanging
by one end of the body to the tent or
twig, as shown in Fig 9. These cater
pillars appear to be affected by one OF
the bacterial diseases hat are known
to develop in many insect larvae when
they become very abundant. The army
worm and common cabbage worm are
frequently destroyed in great numbers
by such diseases. While there appeared
to be more of these disease larvae this
year than last in southern New Hamp-
shire, the disease was not sufficiently
destructive to give great hone for the
immediate suppression Of the outbreak.
The fact of Zach colony being some
what isolated from Others will tend to