Semi-weekly herald. [volume] (Durango, Colo.) 1907-1917, 1910-03-07
THE POTATO BEETLE.

The potato beetle is such com
mon pest that a description scarcely
seems Necessary, but since other in
sects are often mistaken for it. it may
be well to give brief account OF it,
The adult beetle is oval in form
about three-eighths of an inch in
length. and just little narrower than
long The ground color is yellow The
upper wings are marked by ten black
lines running lengthwise
The adults live over winter in the
ground to the depth of six to ten
inches or more. Where the ground
is loose they have been found to the
depth of several feet.
In the spring the beetles appear
about the time that the potatoes
break from the ground, and in a few
days the egg laying begins. The eggs
are bright yellow in color and are
laid in patches ON the under sides OF
the leaves. Each patch contains from
fifteen to fifty eggs. They are very
easily discovered by simply turning
over the vines with the hands so that
the under sides of the leaves are eX-
posed. Every potato grower should
make a systematic examination of
the vines by passing through his
fields and turning over the leaves of
two or three hills in each row
The eggs hatch in from four to eight
days, according to the temperature.
The larvae are dark red grubs with
black heads. For the first day or two
they often eat the surface of the leaf
upon which they were Matched. Then
they migrate to the top of the plant
and feed upon the young tender leaves
which are just unfolding.
The ideal moment for the first spray
is just when the eggs are beginning
10 hatch. Fortunately, we now have
siderable wet weather and still enough
clinging to the leaves to do very eff
fective work This is arsenate of
lead.
MS DOiSOli tOIlCS III llt
form of white paste. though some
manufacturers make II powdered
product The arsenical is applied to
the vines in water at the rate of six
or eight pounds of the poison to
hundred gallons of water, or about
three or four pounds TO the barrel.
The best way to mix the poison is TO
weigh out the required amount in
pail, pour in some water. and mix
thoroughly with a stick. Pour off the
top of the mixture into the barrel of
water through a screened funnel. Add
more water to the remainder in The
pail, mix, and proceed as before un-
til all the substance has been dis.
solved.
The best method of application, es
pecially in large fields, is by means
of power sprayer. These machines
are made to spray from four to six
rows with fine, misty spray A fine
nozzle is used and the liquid forced
out with pressure. The pressure is
obtained by gear attachments with
the wheels, II will be best for the
farmer to consult neighbors who have
used these machines and select one
that has given satisfaction elsewhere,
Some of the earlier makes failed to
give sufficient power to make good
spray.
A very effective homemade sprayer
may be made by mounting square
platform on the front wheels OF
wagon. On this barrel is placed
which is furnished with a good hand
spray pump. From the barrel four
leads of hose go to a rod extending
across the back of the platform. Each
hose is provided with vermoral noz-
zle which sprays downward. The noz-
zles are spaced so that one comes
over each row of potatoes The cost
OF this apparatus is about twenty dol
lars, not counting the wagon and
labor.
s. ARTHUR JOHNSON,
Colorado Agricultural College, Fort
Collins.