New-York tribune., 1911-02-22
THE 17-YEAR LOCUST" SCARE
Professor Ditmars Says the Cicada
Really Does Little Harm.

To the Editor OF The Tribune.
Sir: Purporting TO come from the under
signed are number OF interviews relative
to the seventeen-year locust" swarm
of which will appear in Eastern New Jer-
sey during the coming May and June
From a concise statement relative to the
appearance OF these insects and the rather
superficial damage 20 trees that Will re-
suit have grown elaborate and altogether
incorrect alleged statements from me as
70 the "migrations" of these ''voracious"
creatures which will darken the sky and
leave not a green leaf behind them. 1t Is
asserted that crops and the foliage of the
woods will sufer-that many agriculturists
may expect their efforts 10 be for naught
the coming summer
The status Of the situation follows: The
so-called seventeen-year locust" is not
locust. or even distantly related to the true
locusts. which insects belong 10 that order
in entomology which embraces the grass
hoppers Certain species Of true locust
sometimes occur in great swarms. which,
settling over a considerable area Of country.
Gevour every green leaf and sprout. thence
migrate in enormous clouds, partly obscur-
ing the light Of the sun, AMI settle in an
other feeding ground, when is likewise
devastated These very destructive insects
belong to the order orthoptera.
The seVenteen-year locust" or let us
properly call him the sevente year ci-
cada, belongs to the order hemiptera. and
is closely related to the familiar dog day"
or harvest fy, an insect which In these
regions buzzes loudly in the tree tops dur
inc he Iat in ha hot
This insect is also improperly called
locust" Like all of the members of its
order. it is provided with a beak or pro
boscis. The hemipterous insects do not de
your foliage, but obtain their nourishment
by sucking the juices OF plants or the blood
Of animals-the greater number of them by
the former process.
The seventeen-year cicada deposits its
eggs under the bark of small branches or
in the trunks Of very young trees When
the "grubs" hatch they fall TO the ground
and pass seventeen years in a subterrane-
Gus existence. when they crawl up the
trunks OF trees, the skin of the back splits
open and the perfect insect energies. The
life of the latter is only few weeks, and
the only damage done is caused by the fe-
males depositing the eggs, by means OF a
lanceolste appendsge I'm the branches of
trees These branches soon die, and a for
est teeming with a swarm Of the cicadas
looks as II a superficial fire had passed
through IT,
During the time of the last swarm In
Eastern New Jersey William Beutenmtiler.
curator of entomology In the American
Museum of Natural History, and the
writer, who was his assistant at the time
made extended Investigations of the in
sects. In the woods on the palisades of the
Hudson they occurred i'm countless thou
sands. and branches of low bushes sagged
with their weight. The air resounded from
Of the males, which sound never varied in
intensity. and could he heard from the
ferTyboats when several hundred feet from
the slips When the last OF the females had
deposited their eggs. our detailed invest-
cations demonstrated that the oaks had
suffered most. especially the very young
trees but that the damage TO the woods
was by no means serious
a series Of preserved ccadas collected
from that swarm was last summer exhib-
tied i'm connection with the insect collection
in the Geological Park. with an explanatory
label describing the bugaboo of this 10
Gust" Swarms of the destructive. migra-
tory locust do not occur in this part OF the
United States. RAYMOND DITMARS
The New York Geological Park. Feb 70.
1911