36 BULLETIN 959, U. S. DEPARTMENT OF AGRICULTURE. 
each of the orchards; hence there was no chance to determine what 
cumulative effect it might have if used over a series of years and if 
applied to all of the trees in the orchard. Since we have no experi- 
mental data to indicate the cumulative value of the trap the writers are 
not in a position to make any recommendations, but for those who 
wish to give the trap a trial the following method of manufacture is 
suggested. | 
MANUFACTURE. 
The materials needed for the manufacture of the codling-moth 
trap are as follows: Medium to heavy burlap, ordinary black-painted 
or japanned wire screen having 12 meshes to the inch, a folding 
machine such as that used by tinners to fold the edge of tin sheeting, 
and a crimping machine such as that used to reduce the end of stove 
pipe. 
The burlap is cut into strips 6 inches wide and folded into three 
thicknesses by any convenient method. Wetting the burlap will 
make it fold more easily and remain better creased. To assist in 
this, however, it is well to roll the burlap up in flat rolls of any con- 
venient size so that they can be easily handled in the field. 
The wire screen is also cut into strips 6 inches wide and of any 
convenient length, depending on the length of the machine used to 
fold the edges. The edge of each strip should be folded at least 
once, preferably twice, using the folding machine mentioned above 
or any other convenient method. This fold should not be over 
three-eighths to one-half of an inch wide if folded once and not over 
one-fourth of an inch wide if folded twice. It is essential that the 
wire should be folded at least once and preferably twice, as the edges 
can then be crimped much better in the crimping machine and a more 
desirable bulge produced. Both edges of the strip are then run 
through the crimping machine, which should be set to make a fairly 
deep crimp without cutting the wire and about three-fourths to one > 
inch from each edge. This crimp will aid greatly in giving, as stated 
above, a desirable bulge to the wire when it is applied to the tree, 
and further it will allow for the expansion of the tree trunk as it 
grows throughout the season. As the wire comes from the crimping 
machine it can well be rolled up into small rolls, which will greatly 
assist in keeping the crimp intact and also facilitate the manipulation 
of the wire in the field. If the crimping machine mentioned above 
can not be had, some other method, such as tucking the edges, must 
be adopted to give the desired bulge and to keep it away from the 
burlap on the tree. 
APPLICATION. 
The materials needed for the application of the codling-moth trap 
to the tree are as follows: A supply each of burlap and wire screen 
prepared as described above, a supply of slate nails about an inch or 
