THE PECAN LEAF CASE-BEARER. 



The results of these experiments are as follows : 



17 



Table XI. — Spraying experiments for the destruction of hibernating larvx of the pecan 

 leaf case-bearer at Monticello, Fla., in 1913. 



Plat 



No. 



Number 

 of trees. 



Treatment. 



Date 

 of appli- 

 cation. 



Results. 



I 



V 

 VII 



11 



10 

 14 



Commercial lime-sulphur 

 solution, testing 33° 

 Baum6, at 1 gallon to 8 

 gallons of water. 



Miscible oil at 1 gallon to 20 

 gallons of water. 



1913 

 Mar. 3 



Mar. 25 



■10 per cent of the larvae emerged from hiber- 

 nacula. Buds and foliage very seriously- 

 damaged by larvae. 



75 per cent of the larvae emerged from hiber- 

 nacula. Buds were badly damaged by 

 larvae. 



Practically all larvae emerged. Nearly 

 every bud was either totally or par- 

 tially destroyed. Some trees were com- 

 pletely defoliated. 









Neither the lime-sulphur solution nor the miscible oil gave satis- 

 factory results, but of the two, lime-sulphur was the better. In 

 this series of experiments a proprietary insecticide consisting of 

 distillate oil, tobacco, and soap, and another one consisting princi- 

 pally of oil were tried at dormant strengths in Plats II, III, and IV, 

 which are not included in Table XI, and both of these were found 

 to be ineffective against the hibernating larvae. 



On February 15, 1913, in the Pabst orchard at Ocean Springs, 

 Miss., fifteen 10-year-old trees were sprayed with commercial lime- 

 sulphur at 1 gallon to 8 gallons of water, and on the same date six 

 10-year-old trees were sprayed with miscible oil at the rate of 1 gal- 

 lon to 15 gallons of water. Since it was impossible for the writer to 

 make observations on these sprayed trees because of stress of work at 

 Monticello, Fla., Mr. Chas. E. Pabst, of Ocean Springs, Miss., was 

 requested to report the results of these experiments. In his report 

 he stated that there seemed to be a slight benefit derived from the 

 lime-sulphur treatment, but so far as could be determined the 

 miscible-oil-sprayed trees were as badly infested with larvae as the 

 trees that were left untreated. 



In order to obtain additional information on the two most common 

 dormant season sprays, a series of spraying experiments was con- 

 ducted at Ocean Springs, Miss., and another at Monticello, Fla. The 

 results of this work are shown in Tables XII and XIII. 



