14 FARMERS’ BULLETIN 1741. 
cents to $1.05 per acre when the usual price is paid for poison, the 
use of machine, the services of the operator, and the labor of the 
team and driver. Spraying does not take the place of spring cultiva- 
tion in improving the condition of the soil and hastening the growth 
of the crop, nor does cultvation take the place of spraymg in pre- 
venting the work of the weevils. The two operations are independent 
of each other, and in many cases both are desirable. 
PASTURING. 
If spraying is out of the question, the first and second crops may 
be protected by destroying the eggs after they have been laid in 
green stems, or the small larvee after they have hatched and begun 
feeding in the tips, by pasturing the field. The success of this as a 
method of killing the insects depends upon managing the grazing 
in the right way and continuing it until most of the eggs have been 
laid; that is, until after the usual cutting time of the first crop. 
Instead of being pastured over the entire area at once, the field 
should be divided into two or three lots, with fencing suitable for 
the kind of live stock that is to be used, and the lots should be 
pastured alternately, so that each, after being eaten down close to 
the ground, will have a chance to grow up before the animals are 
turned in again. The number and size of the lots should be propor- 
tioned to the producing power of the field and the number of ani- 
mals to be pastured, so that each lot may be grazed close to the 
ground about once in two weeks. 
The pasturing may begin as early as the growth of the alfalfa will 
permit, and the change from each lot to the next should be made as 
soon as the larvee which have developed in the next lot begin to feed 
upon the plants. On the other hand, the change should not be made 
until the lot which is being pastured has been grazed close. The 
number of animals which are necessary is regulated by these require- 
ments, varying at different times with the rate of growth of the 
alfalfa. It may sometimes be advisable, when the stock has eaten 
most of the lot clean but allowed the plants to grow tall in certain 
spots, to mow these spots rather than to compel the animals to graze 
them. 
The work may be considered finished as soon as most of the weevil 
eggs have been laid, which means a little later than the usual cutting 
time of the first crop. A good, practical method of deciding this 
question is to continue the pasturing until the lot containing the 
oldest growth continues free from signs of larval feeding past the time 
when the appearance of larve is to be expected, according to the 
experience of the season. 
The area which can be protected from the weevils in this way is . 
limited by the amount of live stock available. Three and one-half 
i 
