CHAPTER XX. 



SHADE TREES 



FOR DIFFERENT PURPOSES AND ELEVATIONS 



The importance of shade trees in the tropics is impossible to 

 over-estimate; they are essential to the planter for his crops, and 

 are a boon to man and beast on account of the shelter they afford 

 from the sun, as well as for their effect in tempering the atmos- 

 phere. Most crops in the tropics require shade at some stage of 

 their growth, some more or less permanently, especially at low 

 elevations, where also bungalows or other human abodes are 

 improved in comfort by a certain amount of protection from the 

 powerful rays of the tropical sun. Shade trees enhance the beauty of 

 oiir surroundings, and render the atmosphere cooler and healthier by 

 checking radiation from the soil. In towns as well as in malarial 

 districts, the hygienic effects of suitable and well-grown trees are 

 well known. It is a mistake, however, to plant trees or shrubs, 

 especially such as have adaptations for collecting water, as sheath- 

 ing leaf-bases or spathulated inflorescence, too near houses, for 

 they harbour mosquitoes and thereby encourage malaria. Certain 

 trees, as Spathodea, may also be a source of danger from their 

 liability to be blown down by wind, while others (as species of 

 Ficus) are objectionable on account of their extensive root system. 

 Others again, as Casuarina, frequently block gutterings, drains, etc., 

 by the almost constant dropping of leaves. 



Qualities of Good Shade Trees. The suitability of trees for 

 purposes of shade depends much on local conditions and individual 

 requirements. Some trees may also serve other useful purposes in 

 addition to providing shade or shelter ; thus, certain kinds which 

 yield edible fruit or other useful product may in some localities be 

 also used to combine shade. In parts of India, Mangoes and other 

 fruit-trees are employed for this dual purpose ; while in some 

 European countries the leasing of fruit-trees which have been 

 planted along public roads is a valuable source of revenue to their 

 respective governments. The most essential qualities of a good 



