91 
After the larvae have collected under the bands tlu^y must be killed 
or the Vjands will become a positive aid to the insect. The usual 
method of examining the bands is as follows: One end is removed 
from the nail and rolled back upon itself around the tree. As the 
cocoons, larva\ and pup^e are exposed they are cut in two with a 
sharp knife or crushed. Many methods have been devised })y which 
these bands can be collected in wagons and brought to a central place, 
where the}' are put in hot water, run through wringers, or somr other 
device used to kill the larvi\i; but in view of the fact that many of the 
worms will crawl out in transit, and comparatively few of them 
remain attached to the l)ands, these methods must give wa}' to the 
one described. Another important point is the length of time which 
should intervene between the examination of bands and the killing of 
the larvae. This time depends entirely upon the length of time which 
it takes the larva to emerge as a moth after having left the fruit. In 
the warmer sections of the West <! or 7 days has been recommended. 
B}' extensive experiments carried on l)y Professor Gillette and the 
writer it was found that practically none of the moths issue until 
after 11 da^^s from the time the}' entered the bands. The data upon 
which the recommendation of 6 or T da^'s was based have in some 
cases been found to be quite inaccurate. AVhen the trees were exam- 
ined not all of the larva3 were killed, and the second week afterwards 
some of them were found to have emerged, and from this the conclu- 
sion was reached that some of them went through the cocoon stage in 
6 or 7 days. The experiments by the writer and Professor Gillette 
have been found in practice to allow a small number of moths to 
escape. A person examining bands frequently can easily tell whether 
the time is too short or too long. If the time is too long, man}' 
empty pupa cases will be found projecting from the band, whereas if 
the time is too short most of the insects will be found in the larval 
stage, not having had time to transform to pu})a\ 
EXPENSE OF BANDING. 
When compared with tlu^ cost of spraying, banding is comparatively 
expensive. One man can (wamint^ the ))ands and kill the larva' on 
about 300 trees in one day. Counting his wages at SI. 50 per day. we 
find that it costs about ^.') a tliousand trees inv one examination, which 
is about half the cost of one spraying. The bands should be placed 
upon the trees in the spring at a])out the time the (^arliest larva^ of the 
first generation ])egin to Umivc the fruit. This time is usually alH>ut 
two weeks after tlie iirst wonny fruits hiwc l)een noti^d. and in south- 
ern Idaho is about Juiu> 1'). It is always well to apply the bands a 
week or so earlier than there is any necessity for. The bands should 
be examined every ten days and the larva^ which have collected in 
them killed. This makes about ten or eleven examinations of the 
bands in the course of the season. KxaminatiiUi ixUov the tirst week 
