RANGE AND CLIMATE. 



the evaporation was equal to 12' I inches per annum. This experiment was 

 made to estimate the effect of wind on soil moisture ; in this determination 

 the wind-exposed water was sheltered from the direct rays of the sun. 



When the wind reaches a high velocity mechanical damage to the leaves 

 is very evident, and when the wind becomes cyclonic the whole growing crop 

 may be destroyed, as happened in Mauritius in 1892. 



To a certain extent the effects of wind may be mitigated by the judicious 

 planting of wind breaks. Such a wind break of Casuarina equisetifolia is to be 

 found on a very large scale at Lihue Plantation in the Hawaiian Islands. The 

 sea front of this estate is girdled by a wind break extending for several miles, 

 and covering altogether 600 acres. When in Demerara, the writer always felt 

 that no inconsiderable benefit would accrue if on those flat, wind-swept estates 

 all the cross dams and other available areas were planted with trees. 



Variety and Climate. It may be said that all varieties of cane- 

 attain their maximum growth in the more essentially tropical districts ; some 

 varieties, on the other hand, fail entirely when removed to these latter 

 districts. 



It seems probable that adaptability to a colder climate is a characteristic 

 of the red and purple canes. In a subsequent chapter it will be shown that 

 the light and dark Cheribon (Transparent, Bamboo, &c.,) canes in all probability 

 originated from striped canes. Stubbs 9 states that in the relatively cold 

 climate of Louisiana a plantation of striped canes if not renewed tends to pass- 

 into one of all purple canes, and classes this phenomenon as a case of the 

 " survival of the fittest," attributing to the purple colour a greater capacity to 

 absorb heat. 



The cane known as Cavengerie, Port Mackay (in Mauritius), Louzier (in 

 the Argentine), Po-a-ole (in the West Indies), is also another instance of a 

 dark coloured cane being adapted to a cold climate. In the less tropical 

 portions of South America this variety is one of the canes most widely 

 grown. 



In the Hawaiian Islands the Lahaina cane forms the bulk of the crop on 

 the irrigated plantations in the arid districts, chiefly at a low altitude ; it is 

 replaced by the Yellow Caledonia on the rainfall plantations situated mainly 

 at a higher level, and hence with a colder climate. A peculiar case of suit- 

 ability to climate is to be found in the D. 74 cane which has conferred so great 

 a benefit on the Louisiana industry ; suitability to the climate of Louisiana is 

 in this case due to the early maturity habit of the variety. The adaptability 

 of a variety to a cold climate does not in any way imply that it will fail in 



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