Page 2^ 



BETTER FRUIT 



February 



(c) Comparison between arsenate of 

 lead and paris green, Plat 4 being 

 sprayed with arsenate of lead upon prac- 

 tically the same dates as Plat 5, where 

 only paris green was used. An exhibit 

 of the results may be seen in Table X. 



(d) Comparison of the home-made 

 with the commercial arsenates of lead 

 and a comparison of the efficiency of 

 the different brands of commercial arsen- 

 ates of lead upon the market. 



A more disagreeable and unfavorable 

 spring for spraying is rarely seen in 

 Ozarks than that which prevailed in 1908, 

 when the experiments reported were 

 carried out. Hard, beating rains fell 



RAINFALL DURING MONTHS OF SPRING 



SPRAYS 



(INCHES) 







Day 



April 



May 



J line 



1 







22 



2 







.44 



.3 







.04 



4 



.13 



.29 



.64 



5 : . . . 



1.01 



2.50 



.11 



6 





.46 



.01 





1.68 



.05 



.01 



8 



.64 





.05 



9 



.30 





.04 



10 



1.05 





.01 



11 



.02 



.09 





12 





.70 



'.si 



.68 



13 





.71 



14 



.15 



1.20 





15 



.16 







17 



.34 



'.09 



.32 



IS 



.01 



.15 











3.39 





23 





.01 





24 



1.47 



'.64 



26 



.98 







29 



1.12 



.60 



'.20 



Totals 



9.0G 



10.24 



3.72 



RAINFALL 



AT OLDEN 





Spring of 1908 Compared with Previous 



Years 



Year 



April 



May 



June 



1908 



9.06 



10.24 



3.72 



1907 



, , 5.07 



7.78 



5.72 



1906 



4.19 



2.58 



3.93 



1905 



4.13 



7.40 



3.89 



1904 



5.59 



3.90 



6.61 



1903 



3.92 



8.45 



2.10 



often, either so as to interrupt the spray- 

 ing or immediately after spraying had 

 been completed. A heavy rain of more 

 than an inch fell on April 29, tempo- 

 rarily putting a stop to this first and 

 most important treatment. On the same 



day of the spraying given May 12 nearly 

 an inch of rain fell, and on the two fol- 

 lowing days an average of about an inch 

 precipitation per day was recorded. Dur- 

 ing the month of May, when a majority 

 of the early sprays were given, there 

 was a total rainfall of 10.24 inches dis- 

 tributed over thirteen days of the month. 

 On the 5th of May there was a down- 

 pour of 2.5 inches, and on the 22nd 3.39 

 inches fell within twenty-four hours. 

 During the month of June there were 

 fifteen days of rainfall. The rainfall for 

 the month of April in 1908 was 9.06 

 inches — greater than for any month of 

 April in the five preceding years, for 



which period the average was but 4.58 

 inches. The rainfall for the month of 

 May in 1908 was almost twice the aver- 

 age for the five years preceding, which 

 was but 6.02 inches. 



These weather records are cited to 

 shov/ the unusually adverse conditions 

 under which the results to be discussed 

 were secured. Many times when the 

 sprayings were given the ground in the 

 orchard, from the almost incessant rains, 

 was so soft that a load of the spray 

 mixture could scarcely be hauled over it. 

 The comparatively light weight of the 

 power outfit used and the broad tires and 

 high wheels of the wagon were at times 

 the only things which prevented delays 

 in sprays at critical seasons. 



The records of the rainfall were kindly 

 furnished by Mr. John C. Evans, Jr., 

 manager of the Olden Fruit Company, 

 and at present volunteer observer for the 

 U. S. Weather Bureau. 



It is a well known fact that spraying 

 experiments, conducted against insects 

 which fly readily for considerable dis- 

 tances, to represent the true value of 

 the sprays in comparison with the trees 

 not sprayed, must be carried on upon 

 orchard blocks of considerable size. The 

 plats must be of sufficient size that the 

 trees selected from which to measure the 

 effect of the sprays may be so remote 

 from the unsprayed trees that the differ- 

 ent plats will not be mutually influenced. 

 This important factor was first taken 

 into consideration in experiments con- 

 ducted against the codling moth by Dr. 

 Forbes in Illinois in 1887, and its bear- 

 ing upon experiments against the cur- 

 culio on apple was worked out by him 

 and reported in detail in 1905. 



In laying out the different blocks for 

 spraying in the experiments at Olden 

 this precaution for accuracy was con- 



FiGURE 12— YOUNG APPLES, SHOWING ON LEFT CALYX LOBES OPEN AND IN 

 CONDITION FOR FIRST SPRAY; ON RIGHT, CALYX LOBES CLOSED AND ALMOST, 

 NOT QUITE, TOO LATE FOR FIRST SPRAYING 

 (After Ouaintance, U. S. Department of Agriculture Year Book, 1907) 



