' 164 



packs as " fancy" grade. By eai ly atiention to pruning, the trees need 

 never be allowed to grow too close in the centre. 



Renewal of Tops. — There are some groves of old orange trees that 

 do not respond to the best treatment that the owners can give them. 

 Under such circumsti^nces, the most effective wBy to stimulate new life 

 and vigour is sometimes to remove the entire top, leaving enough of each 

 of the main limbs to distribute equally the suckers that will afterward 

 make the new top of the tree. If the tops are only thinned out and 

 but partially cut back, there will be a proportionate amount of feeble 

 growth and a corresponding lack of productiveness. An old orange tree 

 will rapidly produce a new top, even when cut back to a mere stump. 

 It is soon in a condition to bear again at its full capacity. When the 

 roots are healthy and the soil is properly cultivated and fertilized, the 

 orange tree appears able so produce several generations of tops on one 

 stock. But it will generally be found that the trouble with old, non- 

 productive trees lies in the root-system, or in the management of soil, 

 or in both. Thorough investigation of roots and soil should be made 

 before any severe cutting or pruning of the top is resorted to. 



Except as noted in preceding paragraphs, all trees should be trained 

 low for protection against fro-t, heat, and wind, and to aid the gather- 

 ing of fruit. Heavily-laden branches are generally propped to pre- 

 vent breaking down, as the loss from dropping and splitting is so 

 great that the trees cannot be safely lightened by thinning of fruit 

 •when small. 



CULTIVATION AND IRRIGATION. 



During the past seven years the substation grove has been ploughed 

 deeply at least twice north and south one year, and twice east and 

 west the next. Every year the plough turns up masses of fibrous roots 

 that grow ju*t below the reach of the cultivator teeth, in the strip of 

 land between the trees in the rows running in the direction of the last 

 ploughing. These roots grow from five to twelve inches below the sur- 

 face during the winter and spring when the soil is kept moist by rains. 

 Their presence shows the upward tendency of tiie feeding roots of 

 orange trees when left to grow naturally under favourable conditions. 



The extent to which the root-systems of orange trees can be in- 

 fluenced by orchard treatment seems to be very limited. 



Ihe detp-rooting tendency of the sour orange is observable in both 

 light and heavy soils, while the roots of the sweet orange, and in a 

 lesser degree those of the pomelo grow near the surface in all kinds of 

 soil during the seasons of their most rapid growth, and the only way 

 in which they can be forced toalower depth is to plough deeply and ap- 

 ply irrigation water as low as practicable. As orchardists cannot with 

 present facilities afford to plough deeper than ten or twelve inches, the 

 fibrous roots will mostly be found just below that depth. Even after 

 trees become old and well established their fibrous roots continually 

 seek the surface soil, unless deep ploughing and deep irrigation are per- 

 sistent ly practised. One orchard near Fomona, which has been ploughed 

 deeply from the time it was planted and irrigated in deep furrows, 

 bore lour and a half boxes of fruit per tree at the age of eleven years. 

 An adjoining orchard that was never ploughed, but was cultivated fre- 

 quently and irrigated in furrows made with a "bull-tongue" attach- 



