82 BULLETIN 959, U. S. DEPARTMENT OF AGRICULTURE. 
. TABLE 21.—Spraying schedules for the codling moth in the Grand Valley of Colorado. 
Applications. 
iB ite IgGl 
ot eae Medium . 
Spray Lightin- |; nfestation | Heavy in- 
aay x te : 3 enage festation | ond with | JeStation 
Application. we Time of application. and with .With | and with 
Ssce varieties | Y@tleNes | Varieties 
tion : on which | == 
on Which | the codling| 02 Which 
the codling tions the codling 
moth is aades™ mothis — 
| not diffi- Tcl Rae difficult 
| cult to ealnin to 
control. | a ate al control. 
. | 
Calyx spray ---.-...- A. Begin when 90 per cent petals have | First___... Hirshose se First. 
crops and finish before calyces | 
close. 
Cover spray, first B. 3to4 weeks after A, just previous to. Second..... Second.-...| Second. 
brood. time when Srst-brood larve begin to ; 
hatch. 
Wot. see eS Cz 10 to 12 days after B, just previous to |___._______. Thirds .-) Third. 
hatching of first-brood larve in large 
numbers. 
WO Sheree cee ae D. | 15 to 17 days after B, just previous to | Third_...- 
hatching of first-brood larve in |; 
maximum numbers. 
Monti tes. ets E. | 10 to 12 days after C, for late hatching |___..__. s.... Fourth...-} Fourth. 
first-brood larve. 
Cover spray, second! F. 9 to 10 weeks after A, iust previousto | Fourth.... Fifth...... | Fifth. 
brood. time when second-brood larve begin | 
to hatch. : 
WOE essen G. 24 t0 26 days aiter F) just previous to jc 2-22-26 | SExthe 
hatching of second-brood larve in | 
large numbers. 
Coverspray,second! H. 34 to 36 days after F, just previousto | Fifth...._. Sixths 55% 
and third broods. hatching of second-brood larve in | 
maximum numbers and for protec- | 2 
tion against third-brood larve. 
iD Reena Se meee I. |15 to 17 days after G, for late hatching | Sep Phe ae 2H Ry 33 5 ce cS | Seventh. 
second-brood larve and for protec- | 
tion against third-brood larve. 
From the foregoing schedules it will be seen that the first or calyx 
treatment is given in each schedule and that it should be started when | 
about 90 per cent of the petals have dropped, and should be finished 
before the calyces close. The object of this application is merely to 
fill the calyx or blossom end of the fruit so that the worms that 
attempt to enter by way of the calyx will be killed by the poison 
lodged therein. Any spray applied after the calyx cups have closed 
will have no value in checking calyx worms. This application should 
be very thorough, and, for the sake of speed, it is advisable to use a 
spray under a pressure of about 225 pounds. 
Schedule I consists of four cover sprays, the first of which should be 
applied three to four weeks after the calyx application, just previous 
to the time when the first-brood larve begin to hatch. This appli- 
cation will serve to coat the young fruit and foliage with poison as a 
protection against the early hatching worms. The second cover spray 
for the first brood should be applied 15 to 17 days later, just before the 
first-brood larvye hatch in maximum numbers. The first cover spray 
for the second brood should be made 9 to 10 weeks after the calyx 
treatment, just prior to the time when the second-brood larve begin 
