160 The Philippine Journal of Science ms 



tility of the cane fields naturally resulting from long-continued 

 planting without replacing the food elements by fertilizer. This 

 phase of the agricultural problem is considered briefly in the fol- 

 lowing resume of experiments carried out during 1910 at the 

 College of Agriculture, near Los Banos, Laguna Province, Luzon. 

 The object of the investigation was to settle the various ques- 

 tions enumerated below: 



1. The effect of prolonged soaking on the cane seed. 



2. The effect of late planting. 



3. The results obtained by various methods of planting. 



4. The influence of various fertilizers on the cane as manifested 

 by: (a) suckering; (b) growth of cane in length; (c) growth 

 of cane in circumference; (d) production of leaves; (e) color of 

 foliage, and (/) yield of stripped cane per hectare. 



The purple variety of cane was employed throughout, as it 

 appears to be superior to the white. 



The experimental plots were located on an old sugar plan- 

 tation formerly belonging to Mr. Agripino Salva Cruz. The soil 

 was a sandy clay loam with surface layer about 25 centimeters 

 deep and clay subsoil. The field was never artificially fertilized, 

 but had been in continuous use for fifteen years as a sugar ha- 

 cienda. The land was allowed to lie fallow during the year pre- 

 ceding the experiments, and planted with purple cane in the 

 early part of June, 1910. The tops used for planting were ob- 

 tained from Negros a month previous, and immediately placed 

 in running water. Thus the period of soaking was excessive, 

 and the date of planting very late. 



The field was then divided into 6 plots designated as V-A, 

 V-B, VI-A, VI-B, VII-A, VII-B. Plots V-A, VI-A, and VII-A 

 were unfertilized and served as checks on the 3 corresponding 

 fertilized plots designated as B. The rows of all corresponding 

 plots were continuous from one to the other. 



The remaining seed tops were planted in 4 plots, I, II, III, and 

 IV. All tops were about 30 centimeters long, and bore approxi- 

 mately 6 buds each. The fertilizers used consisted of dried blood 

 and compound fertilizer of ammonium sulphate, potassium sul- 

 phate, and superphosphate of lime in the proportions of 2 : 3 : 5.* 

 Data regarding the amounts of these fertilizers may be found in 

 the subsequent tables. 



Ten plants in each plot were selected from continuous stools in 

 rows of average condition, and carefully labeled. Weekly obser- 



' This fertilizer was furnished gratis by Messrs. Behn, Meyer & Co., Ltd., 

 of Manila. 



