Food for a number of experiments in applying plant-food ma- 

 _ inants terials to the foliage in the form of summer sprays, and 

 176 after seeing that certain crude-oil emulsions used as 

 dormant sprays had a marked effect in stimulating an 

 increased vigor of the trees the following spring, it was 

 decided to try the effect of a strong solution of Nitrate 

 of Soda as a winter or dormant spray. Caustic potash 

 (potash lye) was also added for the purpose of giving 

 the spray an insecticide value. The mixture was pre- 

 pared according to the following formula: 



Nitrate of soda 50 pounds 



Caustic potash 7 pounds 



Water 50 gallons 



The experiment was conducted in a Yellow Bell- 

 flower apple orchard owned by Mr. O. D. Stoesser, of 

 Watsonville, Cal. This orchard is situated about 5 

 miles from the ocean shore and is in a district that is 

 more subject to ocean fogs and trade winds than is 

 the main portion of the Pajaro Valley. It is a common 

 characteristic of the numerous orchards of Yellow Bell- 

 flower apples of this particular district that they bloom 

 abundantly, but set only a partial crop. The trees 

 are on a deep sedimentary soil and grow well. 



Seven 12-year-old trees were sprayed on February 

 2, 1912. The application was very thoroughly made, 

 so that all of the small twigs were drenched. About 

 7 gallons of spray solution were applied to each tree. 

 Adjoining this row on one side was a check row of seven 

 trees which received no winter spraying, and on the 

 other side were several rows of seven trees each which 

 received various applications of crude-oil emulsions 

 and soaps. For the purpose of gaining some idea of 

 the effect of Nitrate of Soda used as a fertilizer, 50 

 pounds were applied as a surface dressing to one vig- 

 orous tree selected from the row adjoining the Nitrate- 

 sprayed row. This fertilizer was later plowed in and 

 washed down by the rains. 



Effects on Blossoming and on the Foliage 



Notes taken at the time the trees were coming- 

 out in the spring show the following results: 



