The Cecil Whig. [volume] (Elkton, Md.) 1841-current, 1874-06-20
THE COLORADO POTATO BUG.

The Colorado potato bug, or dory-
phora decemlineta, has for several years
past made alarming ravages in the
potato crops of the western section of
the country Some forty years ago, it
was known in the Rocky Mountains,
where it seemed to be indigenous, feed
ing upon the RosTRATUM, or wild potato
When the common tuher was introduced
in that region; the beetle soon attacked
it, and spreading from one field to
another, in 1859 it had reached point
one hundred miles west of Omaha. In
1861 it invaded Iowa, and crossed the
Mississippi in lS64-5
Professor Hall, of Chicago. states
that the beetle lays its eggs on the
under side of the potato leaf. These
are speedily Matched. The larvae, when
full grown. is over half an inch long,
very thick in the middle, and tapering
towards the head and tail. 1t is of
pale yellow color, often dusky or freck-
led on the back, with small blackish
dots, and along each side are two rows
of large black dots. The legs are
black, and the head black and shining.
The mature insect, the beetle itself,
is nearly half an inch long and quar-
ter of an inch wide. Its shape is oval,
very convex above and fiat beneath ;
of hard crustaceous texture, smooth
and shining, and of bright straw
color, the head and thorax being some
times tawny yellow; head and thorax
marked with black spots; the wing
cases with black stripes arranged lon
gitudsnally, FIVE on each case. The
antenn@ are twelvejointed; the first
i've joints are pale or tawny yellow,
the remaining joints black, the last
joint being small, and sunk into the
penultimate one. The legs are tawny
yellow, the hips, knees aud feet being
usually black. 1t requires less than a
month to pass from the egg to the bee
tie state.
Where the bug once gets footing,
it speedily destroys the entire crop. 1t
is believed to effect all it's transforma-
lions in fifteen days, SO that a single
pair would, if unmolested, produce six
ty millions of progeny in single sea-
son. Various modes of preventing its
ravages have been suggested Brush
ing or shaking the Larvae from the
hanlm into vessel is sometimes tried,
but this is laborious and dangerous
operation. busting the leaves with
white hellebore powder is an effective
remedy when it is well done; the pow
der must, however, be freshly ground,
as it loses its efficacy when kept too
long. Paris green is also recommend
ed, but both powders are irritating to
those applying them, while the latter is
extremely poisonous. Birds, it is said,
will not destroy the bugs, as the ema-
nations from their crushed bodies are
noxious even to human beings, and, it
is said, have caused several deaths.
The symptoms resemble those caused
by the bite of rattesnake. The bee
tie has several insect enemies, especial
ly some varieties of ladybird, which
prey upon its eggs and larvae.
There has been considerable alarm
in England lately, lest the pest should
be imported thither in American pota-
toes, and official investigations have
been made in order to determine the
ACCESSIBILITY of prohibiting importations
of the vegetables. The report, how
ever, points out that the larvae of the
parasite are not deposited in the tubers
or conveyed by them, and that with the
exercise of proper care no danger need
be apprehended from bringing Ameri-
can potatoes into this country.