igii 



BETTER FRUIT 



Page 25 



sidcred, as will be seen by the size of 

 the plats treated. In preparing for the 

 counts of apples to determine the results 

 of the spray, ten trees of uniform size 

 and fullness .with fruit were selected as 

 'nearly as possible from the center rows 

 of each plat. The plats being seven and 

 eight rows wide, the trees from which all 

 counted apples came were usually at 

 least six rows distant from the counted 

 trees in the adjoining plat, and in no 

 case was there less than four rows inter- 

 vening. These ten trees centrally located 

 were selected early in the season and 

 a record was kept of the conditions of 

 the windfalls as accurately as possible. 

 Twenty-five different collections of wind- 

 falls in all were made, extending from 

 July 6 to when the fruit was picked in 

 October. Windfall collections extended 

 over a total of three months, with aver- 

 age intervals between collections of from 

 three to four days. 



The matured apples were picked from 

 the ten average trees in each plat on 

 October .5 to October 9, and each apple 

 was at this time taken in hand and given 

 critical examination for insect injuries. 

 The results of counts are tabulated in 

 convenient form. 



Table IV shows the results secured 

 with the use of arsenate of lead against 

 curculio on apple. The calendar dates 

 upon which the sprayings were done- are 

 shown in Table I and the relative dates 

 and intervals between the sprayings in 

 Table IV. 



In plat 1 the first spraying was given 

 immediately following the dropping of 

 the petals, but before the calyx cups had 

 closed. The second spraying was given 

 ten days following, at about which time 

 the first feeding punctures were being 

 made in the little apples by the curculio. 

 but before the first of the codling moth 

 eggs had been laid. The third applica- 

 tion followed in about ten days from the 

 second, being aimed at a time when cur- 

 culio feeding punctures were being made 

 very abundantly and immediately pre- 

 ceding the appearance of the first of 

 the hatching codling moth worms. The 

 fourth spray in this plat was intended to 

 be principally against the second genera- 

 ti(jn of codling moth larvae, and was 

 being applied when the first of the sec- 

 ond generation eggs were found and 

 about six weeks after the third treatment. 



In plat 2 the spraying was in every 

 way similar to that given to plat 1, 



Figure 13— INGRAM APPLES SHOWING PARIS GREEN BURNING AT BLOSSOM END 

 In plat 5, 22.46 per cent of picked apples showed such injury. Practically no such damage from 



arsenate of lead. 



Figure 1-5- 



-DIMPLES IN APPLES FROM EGG-LAYING 

 OF TARNISHED PLANT BUG 

 Apples small and fuzzy. Less than one month from hatch- 

 ing of plant bug eggs. About half size. 



except that the late spray applied in 

 July, when the second generation eggs 

 of codling moth were appearing, was 

 omitted, and only the early sprays being 

 directed with special reference to the 

 curculio were given. As will be seen in 

 the last column of the table, there was 

 no benefit secured by the additional late 

 spray. On the other hand, the three 

 sprays applied as indicated in plat 2 gave 

 97.6% of the picked apples free from 

 curculio crescents, while plat 6, the 

 unsprayed block, gave only 54.5% free 

 from such injuries. 



In plat 3 the first spraying was given, 

 as with the others, after the petals were 

 of¥ and before the calyces were closed. 

 The appearance of the first codling moth 

 eggs of the season was the signal for the 

 application of the second spray, and in 

 this season followed the first spraying 

 about three weeks. In about two weeks 

 codling moth eggs of the first genera- 

 tion were approaching maximum num- 

 bers, at which time the third spraying 

 was given. About one month following 

 the third spraying, eggs of the 

 second generation codling moth 

 were seen appearing, and the 

 fourth spray was applied. 



Plat 4 received three sprays in 

 all, the same sprays that were 

 given plat 3, except that the late 

 application in July was entirely 

 omitted. It will be seen that 

 96.5% of the apples at picking 

 time in plat 3 were free from 

 curculio, while plat 4, sprayed 

 only three times, gave 96.2% of 

 picked apples with no crescent 

 injuries from curculio. The late 

 spraying in this case was also 

 found unprofitable, as the three 

 early, thorough sprayings yielded 

 within one-half of one per cent 



of the results secured against curculio 

 with the additional late spray. 



As already noted, the spraying in plats 

 1 and 2 was done more especially with 

 curculio in mind, and that in plats 3 

 and 4 with special reference to the cod- 

 ling moth. We find that four sprays on 

 plat 1 after the former plan gave 97.5% 

 picked apples free from curculio cres- 

 cents, and four sprays in plat 3, after the 

 latter plan, gave 96.5% picked apples 

 without curculio crescents, a difference 

 of 1% favoring the former. Again, a 

 comparison of plat 2, receiving three 

 sprays under the plan, also gave a better 

 grade of fruit than three sprays after the 

 second plan, the increase in apples free 

 from curculio crescents being 1.4%. Thus 

 in both sets of comparisons a slight 

 increase in fruit free from damage by 

 curculio was secured in plats with early 

 sprays at short intervals. As stated, in 

 the orchard under experiment, the cur- 

 culio injuries were naturally more abun- 

 dant than were those from codling moth. 



Table V will show the results that were 

 secured from the different schemes of 

 spraying in preventing codling moth 

 injury. The explanation of the dates 

 of spraying of these four different plats 

 having been given in the description of 

 the preceding table, they may be omitted 

 here. From Table V it will be seen that 

 so far as controlling codling moth is con- 

 cerned in this orchard, none of the 

 sprays applied late were of any practical 

 value, and virtually the same results were 

 secured with only early sprays. Three 

 sprays, applied as indicated in plats 2 

 and 4, each gave better than 99% picked 

 apples free from codling moth worm 

 holes, though it may also be seen that 

 in plat 6 the damage to the picked apples 

 from codling moth was only about 15%. 



