The Glasgow courier., 1916-08-18

HlOuH1IAS d UdIIISIs LUZ cApcTlcIlCe mas
not shown that it spreads faster along
rivers than across mountain ranges.
Nevertheless, it is now many miles
nearer to important alfalfa growing
districts which have hitherto felt safe
from it's attack.
Description of Weevil
A description of the alfalfa weevil
and methods of combating it's ravages
are contained in new publication
of the department, Farmers Bulletin
TAI. The spread of the pest has, as
a matter of fact, been slower than
was at one time feared, but it's pro-
gress has been steady. In Utah and
in small portions of Idaho and Wyom-
ing, where it now exists, it has caus-
ed at times loss of so per cent of
the first cutting Of alfalfa and total
loss of the second cutting.
In order that farmers in those Sec
tions in which the weevil has not yet
appeared may be able to recognize
the pest and to protect their crops
from it, the bulletin contains details
of its habits, and of it's appearance
in the various life stages. The weev-
il is most easily discovered in the form
of the full-grown larva. 1t is then a
green worm-like creature one-fourth
of an inch long with black head and
faint white stripe down the middle
of the back. 1t feeds upon the leaves
of alfalfa mainly during late May,
June, and early July and may be
found by sweeping the tops of the
plants with an insect net or by look
ing tor the notches in the leaves
where it has fed. When the larvae
are numerous they destroy most of the
tender growth and cause the tops to
appear white, making the field look
as if frostbitten when viewed from
distance.
The adult insect is an oval, brown
beetle three-sixteenths of an inch
long, with prominent snout Its
color frequently is nearly black. This
beetle is harder to discover than the
larva, but, on the other hand, it is
present in the field the whole year
around. In winter it can be found by
digging about the crowns and rotts
Of alfalfa plan.s.
The alfalfa weevil does not hiber-
nate definitely When the weather
is cool the adults are quiet, but with
warmer temperatures they quickly re-
sumo their activities. Egg laying
begins in early spring and is usually
ended by June 10. One efficacious
method of controlling the pest there
fore is to destroy the eggs by pastur-
ing the first crop up to that time. A
similar result may be obtained by
cutting the alfalfa green and feeding
it as soiling crop.
II this is not done, the larvae hatch
in large numbers about the last week
of May, or earlier, and eat the alfalfa
leaves so rapidly that the plant is un-
able to outgrow the injury. After
the field is cut the larvae which have
been feeding upon the first crop gath
er upon the buds of the stubble and
frequently consume all of the second
crop. BY that time most of the in
sects have completed their growing
period and have gone into the pupal
or resting stage. The later growth
of the crop therefore does not suffer
from them.
To protect the crop, pasturing, as
has been said, is effective in the early
part of the season. The field should
be divided into two or three lots, and
each lot should be pastured alternate
ly, the animals being left in it until
the alfalfa has been eaten down close
to the ground. The number and size
of the lots should be proportioned to
the producing power of the field and
the number of animals to be pastured,
so that each lot may be grazed about
once in two weeks. Pasturing should
be continued until most of the weevil
eggs have been laid, which in practice
means a little later than the usual
cutting time, for the first crop. This
method has the additional advantage
of providing an economical method of
fattening live stock. Combined with
the proper feed of grain, alfalfa pas
ture is excellent for putting on weight
and it is said that many farms would
probably be more profitable if their
management centered about the pas
turing of stock on alfalfa, with the