122 DISEASES OF CROP-PLANTS 



Considerable fluctuations occur from year to year, and a distinct 

 difference is maintained between the higher and lower levels. 



Sugar-cane has remained the universal crop in default of any 

 other, and the industry was able to survive the period of depres- 

 sion largely by virtue of the North American market for syrup. 



Ratooning for one or two years is the rule in the uplands ; 

 on the drier coastal districts only plant canes are grown. Heavy 

 manuring is everywhere practised, including the use of large 

 amounts of imported sheep-manure and chemical fertilisers. 

 The common rotation crop is sweet potatoes. In the drier districts 

 cotton had for a few years and may have again an important 

 place in this connection. Yams, tannias and eddoes, and cassava 

 are also grown. Corn is grown as a catch crop ; sorghums are 

 raised for fodder and to some extent for grain. Bananas, peas 

 and beans, breadfruit and other local foodstuffs are produced 

 in a scattered way. 



As elsewhere in the islands the only serious affection of 

 sugar-cane is root disease, induced in this case by low rainfall 

 and extreme exposure.* The system of agriculture made necessary 

 by these conditions, as also the epidemic of disease which in the 

 'nineties drove the Bourbon cane out of cultivation, are discussed 

 in the chapter on sugar-cane diseases. 



Cotton is even more than usual an uncertain crop in Bar- 

 bados, owing primarily to the heaviness of the soil. During 

 the flowering and boiling periods a short spell of wet weather 

 is sufficient to cause heavy shedding, and it is common to see 

 fields in which good bearing is confined to borders or patches 

 which happen to be better drained or lighter than the rest. 

 Under these conditions the land needs much more careful pre- 

 paration for this crop than it usually gets or than is necessary 

 in lighter soil. Success over a term of 5'ears has only been 

 obtained in the driest districts and this is qualified by short 

 crops both in wet years and in periods of continued drought. 

 It has been the custom to depend for an important part of the 

 yield on the secondary growth brought out by showers between 

 December and July. The bolls so produced are usually small, 

 but there is much less liability to shedding. The advent of 

 leaf-blister mite has to a considerable extent qualified the success 

 of this system, though the recent adoption of a close season 

 may go some way towards restoring it. 



The usual parasitic diseases of cotton occur, but are not com- 

 monly the source of any very considerable losses. The absence 

 of the cotton stainer causes the internal boll disease to be rare. 



Owing to the dry climate and the open wind-swept nature 

 of the country fungus and bacterial diseases of plants in general 

 are not numerous or usually important. The exceptions are 

 mainly affections of the type of root disease of sugar-cane which 

 depend on the weakening of resistance in their host rather than 

 on humidity. 



* Mosaic disease has now become generally distributed. 



