22 



DRY-LAND OLIVE CULTURE IN NORTHERN AFRICA. 



a troublesome and expensive operation, but otherwise a fairly deep 

 plowing is generally effective. As a rule, the greatest difficulty in 

 getting the land clean and keeping it so is due to the presence of 

 Bermuda grass, the worst weed of the Sfax region. As irrigation is 

 not practiced, except that the young trees are watered by hand during 

 the first one or two summers after planting, it is not necessary to level 

 the land. In the largest plantations it is the custom not to clear the 

 entire surface before planting but merely strips about 12 feet wide, 

 in the centers of which the rows of trees are to be set. These strips 

 are broadened from year to year until the whole surface of the 

 orchard has been freed from weeds and brush. Whenever possible, 

 however, it is preferable to clear the entire area at the outset, since 

 the unreclaimed portion harbors Bermuda grass, which rapidly 

 spreads into the strips containing the rows of trees. 



PLANTING. 

 DISTANCE BETWEEN THE TREES. 



Wide planting, combined with clean cultivation (see Pis. II 

 and IV) , is the chief factor of success in olive culture at Sfax. 

 Fifty years ago the Arabs hit upon the plan of setting out the trees 

 about 80 feet apart each way, thus giving slightly less than seven 

 trees to the acre ; but this small number is said to produce as much 

 oil as do 50 trees at Susa or 60 to 80 trees in northern Tunis. The 

 natives continue to plant at this distance, but there is a tendency 

 among the French owners of orchards to decrease the distance be- 

 tween the trees to 65.5 feet, which gives space for 10 trees to the acre 

 if planted in squares and 11^ trees if planted in quincunx, as is now 

 frequently done by French olive growers. This system of wide 

 planting conforms to the habit of the olive tree, at least when grown 

 under the climatic and soil conditions of Sfax. It is there a com- 

 paratively shallow-rooting tree, a but the roots form a dense network 

 extending horizontally to an average distance, it is said, of 25 feet in 

 every direction. The root systems of two olive trees at Sfax 80 feet 

 apart have been observed to meet. 



Great care is taken, even by the natives, to secure a perfect align- 

 ment of the trees and to plant them at exactly equal distances. Con- 

 sequently the Sfax orchards are models of systematic planting. 



a One olive grower at Sfax informed the writer that practically the entire 

 root system is contained in the first 3 feet of the soil. The shallow-rooting 

 habit of the olive at Sfax may be at least partly due to the method of propaga- 

 tion by truncheons, which prevents the formation of a taproot. Rooted cut- 

 tings, such as are used in other parts of Tunis, are said to quickly develop a 

 taproot. There is little doubt, however, that the olive is more shallow rooting 

 than most fruit trees. 

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