New-York tribune., 1900-08-12
A TREE TRIMMING INSECT,
THE CICADA, OR SEVENTEEN YEAR LO-
GUST. AND ITS FONDNEss FOR OAKS.


In some of the suburbs of New-York during
the last three or four weeks the oak trees have
undergone an experience that has mystiied the
uninitiated Boughs, varying in length from
fifteen to twenty inches. have been cut off by an
insect with boring apparatus These boughs
have either been partially broken off and have
hung for day two, until there was wind
enough entirely to detach them, else they
have been completely severed at the outset In
the former case the leaves have usually turned
yellow before they fell to the ground. The foIi-
age remaining on the tree-and this is fully 90
per cent of what was originally there's unaf-
fected by the mischief maker.
Experts have difficulty in recognizing in
these phenomena the operations of the grub OF
the cicada, sometimes incorrectly called the 'sev-
enteen year locust" For reasons best known
to themselves, entomologists apply the term
locust" only to the grasshopper. The cicada is
distanty related to the locust. but it lives in
trees, whereas the true locust finds its sphere
Of activity the surface Of the earth. The
cicada, too has a shriIl song that is usually
heard at evening. This is true Of the katydd' ;
song, and the katydid also abides in treetops.
But the notes of the two insects are not at all
alike.
The life history of the cicada is substantially
as follows: In the larvaI form it remains buried
in the earth, at a depth ranging from two %
twenty feet, for seventeen years. During this
time it feeds on the roots Of herbaceOus plants
and trees by means of a long pointed beak. 1t
is alleged that it also absorbs nutriment through
the hairs on it's proboscis but naturaIists repeat
the statement with caution and apparent mis-
givings- The cicada grub seems to have almost
as many skins 4 onion, but, unlike the onion,
it does not have them all at once. While leading
subterranean existence the grub of the cicada
sheds it's skin frequently. but repeats the per-
formance only once or twice after emerging into
daylight.
The year having arrived for this curious or
ganism to enter upon its more active career,
it burrows upward through the soil late in MAJ,
and as soon as it reaches the surface it climbs
an adjacent tree, preferring an oak. The ascent
is usually effected in the evening. At first the
exterior of the insect is soft and fuzzy, but in
few hours the body and wings become hard. The
female lays her eggs in a groove, which she cuts
in Of the outermost twigs of her place of
abode. These hatch out in about six weeks. In
the mean time there has been some growth in the
wood, and the grub finds itself imprisoned. To
escape, it bores its way out In doing so it
generally sewers the twig, but having done so.
it falls to the ground and proceeds TO burrow.
1t then enters upon the long period of secIuson,
which has given rise to the popular term, 'sev-
6nteen year locust The parents continue 10
move in the upper circles of society Until the
chfs CT autumn terminate their careers.
There Is another cicada which emerges from
the earth thirteen years from the time of its
Matching. This specIes is common In the south
ern part of the United States. while the seven
teen year insect inhaDits the northern part.
But while the period is always exact, either
thirteen or seventeen years, there is scarcely a
year when the cicada is not due in some part of
the country.
The damage which this creature does is not
to be compared with that Of the true locust, or
the army worm, or the tent caterpillar. As soon
as the grub cuts its way out of its birthplace
its ability to do harm has come to an end. In
deed, it is questionable whether the slight prun-
ing which the cicada gives to tree ought to be
regarded as harmful at all, and it is doubtful
whether it would be worth while to try TO fight
the insect. However. that seems to be out of
the question anyhow, for soon as the grub
gets out where poison could reach him he drops
to the earth and is out of his enemys way. 1t
is futile to attack him, therefore.
BERLIN PAPERS ENGLISH.