42 



AGRICULTURAL EXPLORATIONS IN ALGERIA. 



from the re.siilts of mechanical aiuiljse.s. The chita afforded by a num- 

 ber of analyses are given })elow. 



The natural fertility of these sandy soils is not great. They are 

 almost devoid of oroanic matter and after a few vears of cultivation 

 need fertilizing". This is suppliinl hy the Aral)s in the form of manure 

 from donkeys, sheep, and camels. The soils of the date orchards that 

 have l)een planted by the two French companies are also fertilized. 



The followino- table gives the results of mechanical analvses of a 

 mim)»er of samples of soil collected in the Oued liirh region of the 

 eastern Sahara. Chemical analyses have not been carried further than 

 a determination of the water-soluble material. 



Table S. — Mecliunicul (imtliixetf of soils from Ihe Oued Rirli region 'm tlii' Snliara Desert. 



p. 



a 



o 

 ■A 



7686 

 76S7 

 7U83 

 7684 

 7685 

 7665 

 7666 

 7667 

 7668 

 7669 

 7670 

 7671 

 7672 

 7673 

 7674 

 7676 

 7677 

 7678 

 7679 

 7680 

 7681 

 7682 



Looality. 



Oiirir. Hard orust among palms. . 



Subsoil of 76.S6 



Ourlana palm orchard 



Subsoil of 7683 



do , 



Ourlana among 13-year-old palms. 



Subsoil of 7665 



Tougourt amid good alfalfa 



Subsoil of 7667 



Tougourt amid alfalfa 



Suljsoil of 7669 



Tougdurt amid alfalfa 



Subsoil of 7671 



Ta-bes-bes Oasis 



Subsoil of 7673 



Kuda Asli Oasis 



Subsoil of 7676 



Dune sand, border of Djadjat'holt 



Oasis of Zoia de Temaein 



Subsoil of 7679 



Oasis of Zoia de Temacin 



Subsoil of 7681 



=*a 



So 



ca 

 osa 





I 



3.74 

 1.84 

 1.14 

 3.70 

 2.84 

 8.06 

 5.74 

 3.98 

 3.06 

 4.63 

 5.37 

 4.98 

 4.07 

 1.72 

 1.33 

 6.75 

 4.39 

 12. 80 

 4.66 

 .5.90 

 4.24 

 2.60 



21.02 

 29. .52 

 17.46 

 36.84 

 18.74 

 32. 52 

 31.70 

 34.44 

 28. 58 

 27. 71 

 32. 12 

 28. 22 

 28. 33 

 20. 24 

 25.94 

 28. 58 

 20. 38 

 51.54 

 22. 50 

 19.60 

 22. 70 

 19. 12 



C A 



"a 



18.98 

 21. 42 

 49.80 

 29.30 

 36.40 

 33. 56 

 40.94 

 37.98 

 45. 92 

 33. .59 

 33. 27 

 30.91 

 29. 82 

 32.53 

 34.40 

 32. 60 

 26. 42 

 18.40 

 17. 48 

 20. 24 

 39.10 

 30.94 



sa 



31.26 



2 i. 40 



9.16 



9.92 



9.14 



14.02 



11.54 



12.56 



12. 12 



24.01 



20. 15 



22.41 



28. 71 



35. 55 



30.14 



18.22 



28.39 



7.62 



9.04 



8.82 



5.76 



10.60 



SALINE SOILS. 



As in all arid countries, particularly where irrigation is practiced, 

 saline .soils are an important factor in the agriculture of Algeria. 

 Extensive areas of the most fertile land of the colony have been 

 injured by an excess of salts, and the alkali problem is to-day one of 

 the most serious which confronts the Algerian farmer. Drainage is 

 not generally practiced b}^ the colonists in their large irrigation dis- 

 tricts, and the lack of it has been the cause of a great deal of damage. 

 On the other hand, the natives of the Sahara show the utmost inge- 

 nuity and skill in managing salty soils and in irrigating w4th saline 

 waters. There is much in the methods practiced l)y these people that 

 should interest the American farmer and that could be imitated by 

 him with profit. 



