rapid growth; the cultivation of such soil requires but little The 

 labour and can be carried to a sufficient depth, so that deep Cultiva tion of 

 rooting is promoted; whilst the injurious extremes of drought ltrus 

 and water-logging are avoided. 



At the same time, it is undoubtedly true that whilst 

 rich alluvial soils produce citrus trees of luxuriant growth, 

 which often bear enormous crops, the finest and choicest 

 fruits are largely produced upon soils of a much lower grade 

 of fertility. As Rolfs has remarked: 



* { In fertile soils the plant food is seldom properly balanced and 

 present in the condition best suited for producing the finest fruits, nor is it 

 possible to influence the contents or quality of the fruit by applying different 

 forms of chemical fertilizers. If, therefore, a field is normally sufficiently 

 fertile to produce a citrus crop for an indefinite number of years, it is 

 usually impossible to influence the quality of fruit markedly by means of 

 fertilizers. Upon soils which are nearly sterile, however, trees may be 

 started and fed with just such chemicals as will produce the finest quality of 

 fruit. It therefore happens that soils which formerly were considered 

 absolutely worthless for agricultural purposes are now made to produce large 

 crops of most excellent fruit."* 



We are not prepared to endorse to their full logical 

 sequence the views thus expressed; but, with certain limita- 

 tions, they serve to inculcate forcibly the value attaching to 

 the skilled employment of chemical fertilizers in the pro- 

 duction of high-class fruits. 



Selection of Varieties. 



No variety of citrus is suitable for cultivation in all re- 

 gions of what may be termed the citrus belt. Thus, the navel 

 orange, which is pre-eminently adapted for California, is 

 of but little value in Florida. On the other hand, certain 

 varieties of pomelo are of exquisite flavour when fruited in 

 Florida, but are not of the same excellence when grown in 

 California. It is essential, therefore, to test in the district 

 in which it is to be grown the particular variety which it is 

 desired to introduce. 



Indeed, so much will depend upon local conditions and 

 market requirements, that we consider it to be inadvisable 

 to make specific recommendations under this head. Suffice 

 it to say that the choicest varieties, capable at the same time 

 of heavy yields, and those taking a permanently prominent 



* Farmers' Bulletin No. 238, U. S. Department of Agriculture. 



