lOr; FROGHOPPER BLIGHT OF SUGAR-CANE. 



Tarouha. Field 33. Fewer nymphs at bottom of hill where canes 

 are larger and soil darker. (1. vii. 18.) 



Analysis showed a richer soil at the foot of the slope. 



Damage Worse at Bottom of Slope. 



La Fortunee. Field 45 B. V. "Best at top of field and along ridges 

 ivhere soil is better. (27. vi. 18.)" 



Tarouha. Field 3 St. John. "Damaged at foot of hill and not on 

 the hill (1. xi. 19) Sail better on slope.'' 



Orange Grove. South end of field 21-23 worse than North end and 

 former is lower part of slight slope. 



It appears from the above that changes in the soil are usually of 

 suflficient importance to outweigh any advantage or disadvantage that 

 the contours of the field may give in the way of drainage. The question 

 will be discussed further under the heading of soil and drainage. 



THE SOIL. 



In 1850 Messrs. Wall and Sawkins published a report on the geologj' 

 of Trinidad and described with considerable accuracy the main types of 

 soil of the cultivated parts of Trinidad. 



In 1880 L. A. Seheult wrote a paper on " Our Arable Lands'" based 

 largely on the work of Wall and Sawkins, but treating the problem more 

 in its agricultural aspect. For the following notes on the types of 

 soil met with in the sugar districts I am indebted very largely to 

 the above works, but have made alterations and corrections from my 

 own experience in the fields and with the assistance of several 

 geologists now working in Trinidad. 



Fig. 26 shows the sugar districts of Trinidad with the distribution of 

 the soils based on the map given hy Wall and Sawkins in 1860. It is 

 diagramatic and shows only the approximate outlines of the formations. 



This is particularly so in the Naparimas where they are so confused 

 thiit changes occur from field to field. 



