18 



BULLETIN 571, U. S. DEPARTMENT OF AGRICULTURE. 



Table XII. — Spraying experiments for the destruction of hibernating larvse of the pecan 

 leaf case-bearer at Ocean Springs, Miss., in 1914- 



Plat 



No. 



Number 

 of trees. 



Treatment. 



Date 

 of appli- 

 cation. 



Result. 



I 



II 

 III 



32 

 17 

 10 



Commercial lime-sulphur 

 solution, testing 33° 

 Baume, at 1 gallon to 8 

 gallons of water. 



Commercial lime-sulphur 

 solution, testing 33° 

 Baume, at 1 gallon to 10 

 gallons of water. 



1914 

 Mar. 9 



.-.do 



Very slightly benefited. Sufficient num- 

 ber of larvae emerged to do considerable 

 damage to buds and foliage. 



Very slight benefit. A large percentage of 

 larvse emerged from hibernacula and 

 severely injured the buds and foliage. 



Practically all larvae that were not parasi- 

 tized emerged from hibernacula. Buds 

 and foliage were severely injured. 









Table XIII.- 



-S praying experiments for the destruction of hibernating larvse of the pecan 

 leaf case-bearer at Monticello, Fla., in 1914- 



Plat No. 



Number 

 of trees. 



Treatment. 



Date of 

 application. 



Results. 



I 



II 

 III 



12 

 10 



8 



Commercial lime-sulphur 



solution at 1 gallon to 8 



gallons of water. 

 Commercial lime-sulphur 



solution at 1 gallon to 10 



gallons of water. 

 Miscible oil at 1 gallon to 



20 gallons of water. 



Mar. 22,1914 



do 



do 



Slight benefit, but a sufficient number 

 of larvae emerged to do much dam- 

 age to buds and foliage. 



Slight benefit, but many larvae emerged 

 from hibernacula and did considera- 

 ble damage to buds and foliage. 



Practically no benefit derived from the 

 treatment. 



The results, as will be noted in Tables XII and XIII, show that 

 the Hme-sulphur solution at 1:8 and 1:10 gave a slight benefit, 

 but that miscible oil was a decided failure. The number of larvse 

 destroyed by the lime-sulphur treatments was not sufficient to combat 

 this pest satisfactorily. Although it has been suggested and advised 

 by certain entomological writers that this pest can be controlled by 

 the use of lime-sulphur during the dormant season, the results of all 

 the experiments show conclusively that the treatment can not be 

 depended upon as a remedy for the pecan leaf case-bearer. 



spraying experiments against overwintered larvae. 



Experiments at Monticello, Fla. 



The work at Monticello, Fla., was conducted in the pecan orchards 

 of the Summit Nurseries and the Standard Pecan Co. For the spray- 

 ing regular orchard gasoline-power outfits were used and the spray 

 material was applied very thoroughly at a pressure ranging from 175 

 to 200 pounds. The results of the experiments are shown in Tables 

 XIV and XV. 



