OLIVE CULTUKE IN SPAIN. 711 



shelter the land on its lee to a distance of 11,000 meters from its apex. 

 Beyond that point, however, the injurious effects of winds thus impeded 

 is more potent than it would be if the obstacle did not exist. The Sierra 

 of Guadarrama, which rears its crest up to 2,385 meters, shelters its 

 southeast exposure to a distance of 26,235 meters, but beyond that 

 limit the action of the cold wi^ds crossing its summits from north to 

 south is felt most keenly. 



The neighborhood of the sea is by no means prejudicial to olive 

 orchards, and in the maritime zone, wherever the proper conditions of 

 soil and climate prevail, olive culture is carried on in close ijroximity to 

 the shore. The ancient dictum, laid down both by Latin and Arab 

 authors, that olive culture could only be prosecuted within 30 leagues 

 from the sea, has, however, been disproved by modern experience. 



Soil. — It may be laid down as a general proposition that soil adapted 

 to the vine is well suited also to olive culture. The characteristics of 

 such a soil will be looseness and fair permeability, and for the olive it 

 is necessary that the soil and active subsoil should have a depth of at 

 least one meter. A calcareous soil, meaning thereby one which con- 

 tains a large proportion of carbonate of lime, is considered valuable for 

 olive culture, especially so in the south ; in a northern district, where 

 the summer is short, such soils are open to the objection of being cold, 

 as their white coloring prevents absorption of heat. The presence of 

 oxide of iron in siich soil, by giving it a reddish tint, corrects this objec- 

 tion, and it is on such soils usually that great yields are obtained on 

 the high central plateaus and in the north. Both magnesia and sul- 

 phate of lime are eflScient substitutes for carbonate of lime — and some 

 sulphate may always be advantageously applied with the manure. Oil 

 produced on soils poor in these ingredients has usually a greenish 

 tinge, and is not as limpid as oil from soils containing them. Potash 

 is a necessary constituent tor olive culture, and when not present in 

 sufficient quantity, must be artifleially supplied. A tendency to ex- 

 uberant flowering and aborting of the fruit, shows a deficiency of phos- 

 phates in the soil, which must be remedied in order to obtain good 

 yields. 



The hygrometric properties of the soil are an important factor, which, 

 however, must necessarily be appreciated according to the general 

 climatic conditions of the locality. Here it is held that in order to be 

 well adapted to the olive tree, soil should retain its looseness after a 

 rain of forty-eight hours' duration, and that during the hot season it 

 should contain 10 per cent, of its weight in water. 



Peats. — The olive tree is subject to a disorder which some years ago 

 gave rise to considerable controversy, some authors holding that it was 

 caused by insect, while others ascribed it to the agency of a fungus. It 

 goes by different names in the different districts ; in Andalusia it is 

 spoken of as 7)ielera, mangla, melazo, tinuela, tizne (smut), accitillo, etc., 

 and in other parts it is frequently called aegra, negrilla or negrura, all 

 150A 21 



