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be subject to the extremes of drought arid excessive moisture in the soil, 

 or to sudden changes of temperature. Unless means are taken to prevent 

 it, the sudden changes which often occur from severe drought to excessive 

 rain, and vice versa, will cause great variations in the temperature of the 

 soil, and these should be avoided by the cultivator as much as possible. 

 This may be done to a great extent in the first place by trenching and 

 draining the ground thoroughly, so as to secure the most perfect root-bed, 

 and secondly by mulching the surface soil so as to shelter it from the full 

 power of the sun and drying wind In deeply- worked, well-drained land 

 the temperature is higher in winter and lower in summer than in shallow 

 or undrained soil, and it is not so readily affected by atmospheric changes. 

 Consequently, trees growing in deep, well worked, and properly-drained 

 land are placed under the most favourable conditions for making steady 

 growth, are not as liable to injury from frost, and in no danger of 

 becoming injured through their roots getting soddened. Then, as regards 

 the protection of the trees by mulching, the cultivator must bear in mind 

 that when the trees are growing under the most favourable conditions the 

 masses of delicate rootlets or feeders which lie near the surface are not as 

 easily injured by the power of the sun as when the ground is fully 

 exposed, and the supply of moisture lasts much longer. 



DISTURBING THE ROOTS. 



In the cultivation of trees of the Orange family it is a matter of essential 

 importance that the roots should not be disturbed to any great extent. 

 The common practice of digging or ploughing among the roots cannot be 

 too strongly condemned. These operations cannot be performed without 

 destroying a great number of the small fibrous roots, or feeders, a large 

 proportion of which lie near the surface. These roots are all required to 

 supply the trees with nourishment, and if a quantity is destroyed, as 

 must be the case when the surface soil is broken up by either the plough 

 or spade, the loss will be felt more or less. The best plan is, as far as is 

 practicable, never to disturb the surface soil at all, leaving each layer of 

 mulching to lie till it decays ; and the only cultivating implement which 

 should ever be used in an orangery is a hand or light horse hoe to keep 

 down the weeds. 



KEEPING THE LAND CLEAN. 



It is a matter of material importance, in cultivating trees of this family, 

 that the ground should be kept perfectly free from weeds, grass, or any 

 other kind of undergrowth. When weeds are allowed to make headway 

 they absorb a considerable amount of plant food and moisture, which 

 otherwise would be available for the support of the trees. The loss of 

 these materials must necessarily be felt by the trees, and more especially 

 the exhaustion of surface moisture during the dry summer months. 



WATERING IN DRY WEATHER. 

 No fruit trees require so much attention in watering as those belonging 



