THE OLIYE 49 



olive, and so promote its groAvtli; but for this very reason require 

 that the trees should be frequently manured in order to obtain an 

 annual product. It is the want of nourishment in the ground, that 

 causes the olive to fruit only every otliei year, or every third year. 



An irrigated soil loses its fertility quicker than one that is not 

 watered ; so, where irrigation is practiced, it is necessary to fre- 

 quently manure. In general, it may be said that the olive requires 

 the same kind of soil as the vine, and in proof of that we often see 

 them grown together. Excessive moisture is prejudicial, and also 

 in a dry, hard soil the tree contracts, S2:)lits, and leaves the roots 

 gorged with sap. The most favorable soil is an open, loose and 

 fairly fertile one, and should be of at least a yard in depth to give 

 the roots opportunity to extend themselves. 



The olive is fond of a chalky soil, that is, one largely made up of 

 lime carbonates. The carbonate of lime is indispensable to vegeta- 

 ble life; and it is noticed, that the oil from olives grown on a calcare- 

 ous soil, is better than .that from a soil lacking in this element. 

 Chalky soils are cold, because they do not easily absorb the heat of 

 the sun. For the same reason red soils are warm, absorbing and 

 retaining a great degree of heat. The best soil for the olive is that 

 in which lime predominates; and where silica exists, and there is no 

 lack of clay. Such a soil would give passage to moisture, and offers 

 no obstacle to the extension of the roots, and at the same time has 

 consistency enough to sustain the tree and preserve the elements of 

 nutrition. The oxide of iron exists in all soils, but Avhere it abounds, 

 the red color declares it. It is favorable to the growth of the olive, 

 particularly in cold regions. 



Suppose two adjacent pieces of ground in such a locality; on the 

 red soil the olives will ripen, whereas on a light colored one they 

 will not. 



Liebig says, that when at the time of flowering of any vegetable, 

 the soil abounds in phosphates, the fruit sets well, and is started on 

 its road with every advantage; and on the contrary, if these are lack- 



