clTAp. XV CASSAVA 275 



starchy cassava meal and tapioca. There are two varieties Varieties. 



of the plant, one the bitter cassava {Manihot utilissimd) and 



the other sweet cassava {ManiJiot Aipi). The two kinds 



have, however, not very distinct specific characters. Sweet 



cassava may be used as a vegetable without any preparation ; 



but bitter cassava contains juice of a very poisonous nature. 



This poisonous juice, in which there is uiuch hydrocyanic or The poison. 



prussic acid, is fortunately dissipated by heat, and so the °"''-'""^^- 



bitter cassava is commonly cultivated as it gives much larger 



returns than the sweet kind. 



Soil and Climate.— The best soil is a sandy loam which The best 

 must be well drained, for the roots soon decay in water- 

 logged ground. The soil, too, must be rich, for cassava is Manuring. 

 a very exhausting crop, and without manure it cannot be 

 raised on the same land more than two or three years run- 

 ning. The climate should be a hot and dry one, and the Climate, 

 plant thrives best in the lowlands in the neighbourhood of 

 the sea. No shade is necessary, and high winds do not 

 damage the plants. 



Cultivation. — The modes of propagation and cultivation Cutting.s. 

 are simple. Full grown woody stems are cut up into pieces 

 from four to six inches long, and these are set in a slanting 

 direction in the ground, with about an inch left above the 

 surface. Previous to planting, however, the soil should be 

 well prepared by ploughing and cross ploughing ; or, on a 

 small scale, it may be worked up with the hoe or spade. 

 Another plan is to plant the cuttings in small shallow holes 

 filled in with good surface soil, or in furrows made at the 

 proper distances with the plough. The distances vary from Distances, 

 four feet to six feet each way, the wider distances being 

 chosen on the best land. The cuttings will begin to grow 

 in about a fortnight after planting, and the ground must 

 be kept free of weeds until the plants grow up and cover 

 the land with thin vegetation, which they will usually do 

 in about three months from the time of planting. In 



T 2 



