A FORTNIGHTLY REVIEW 



OF THE 



IMPERIAL DEPARTMENT OF AGRICULTURE FOR THE WEST INDIES. 



Vcl,. XIII. No. 317. 



BARBADOS, JUNE 20. 1914. 



Price Id, 



CONTENTS. 



Page. 



Agricultur.al Co-operation 

 and Siiiiill Holdings, Note') 

 on 205 



Agricultural Progress in the 

 Gernum Protectorates... 201 



Cotton Notes: — 



West Indian Cotton ... 198 

 Departmental Reports ... 197 



Gleanings 204 



Gr;ii>e Fruit from East 



Africa, Kxportation of... 196 

 Impcri.d Department of 

 Agriculture. Publications 



of 200 



Imperial De\ elopiiient ... 2<'6 

 Insect and Fungus Notes: — 

 The Use of Carbon Bisul- 

 phide in Emulsion in Mar- 

 tinicpie and Guadeloupe 202 

 Exophthalmus Ksuriens 202 



Manurial Experiments in 



the German Colonies... 201 

 Market Reports 208 



Page. 



Meat Scarcity in Temperate 



Countries ... 201 



Nitrification and Disease 199 

 Notes and Comments ... 200 



Onion Trade 206 



Pig Industiy, Organization 



of 206 



Pine-apple Trade, Canned 190 

 Rainfall and Vegetative 



Rest, Relation between 195 

 Rainfall Vegetation and 



I Conservation of 193 



Rice, Physiology of Geruiin- 



1 ation 207 



Rubber 206 



Report on Agricultural 



Educati<m, South Africa. 



1912 13 197 



Soil and Plant Growth .. 198 



Students' Corner 205 



Sugar Industiy: — 



Syrup Treatment... ... 195 



Tropical Development ... 200 

 VVfst Indian Products ... 207 



Vegetation and the Conservation of 

 Rainfall. 



^^ [T^lJeHE prolonged discussion and controversy in 

 ^tlie South African press on the question of the 

 [supposed increased aridity in that country, 

 has recently turned to a consideration as to whether 

 many of the climatic changes that have undoubtedly 

 taken place during recent years cannot be accounted 

 for by the removal of vegetation. The subject pos- 



sesses particular interest in the West Indies where 

 considerations of a similar kind have received attention 

 in regard to the water-supply in several of these 

 islands. It is now well recognized that the indirect 

 effects of forests and of vegetation in general are 

 economically useful largely as the outcome of the 

 retarding influence exercised by trees and even 

 herbaceous plants on the How of water that has been 

 precipitated. Besides the beneficial effect produced 

 by a forest cover on streams in its immediate neigh- 

 bourhood, it is being increasingly recognized that 

 much of the water retained by the forest bed may 

 slowly percolate in a diffused manner through the 

 surrounding soil, and may serve to maintain a useful 

 degree of moisture in the subsoil of land lying at a con- 

 siderable distance away. This subsoil moisture thus 

 steadily maintained by the distant forest may greatly 

 increase the fertility and drought-resisting power of 

 cultivated lands, and it is conceivable that in many 

 of the islands under consideration, the cultivated 

 lands at the foot of the mountains may derive much 

 benefit from the retentive forest bed situated at 

 the top. 



The question constantly arises as to whether 

 forests appreciably increase the actual rainfall. It is 

 difficult to get a satisfactory answer supported by well 

 ascertained facts. The probability is, however, that 

 forests bv lowering and equalizing the temperature of 

 the air on mountain tops, may to a small extent lead to 

 increased precipitation: this increase however is prob- 

 ably almost negligibly small when compared with the 

 benefits derived from forests as regards conservation, 

 and as compared with the effects of the hills themselves 

 in forcing moisture-laden air into the upper atmos- 

 phere. Indeed, altitude is inseparably associated with 



