UTILIZATION AND RECLAMATION OF ALKALI LANDS. 



473 



(probably between 20,000 and 30,000 pounds) are the two 

 melilots, M. indica, and alba; the latter (the Bokhara clover) 

 is a forage plant of no mean value in moist climates, but some- 

 what restricted in its use in the arid region because of the 

 very high aroma it develops, especially in alkali lands; so that 

 stock will eat only limited amounts, best when intermixed 

 with other forage, such as the saltbushes. The yellow melilot 

 is highly recommended by the Arizona Experiment Station as 

 a green-manure plant for winter growth ; but farther north it 

 is a summer-growing plant only, and is refused by stock. As 

 already stated, very few plants belonging to this family are 

 naturally found on alkali lands, and attempts to grow them, 

 even where only Glauber's salt is present, have been but very 

 moderately successful. 



For most of the legumes the limit of full success seems to 

 lie between 3000 and 4000 pounds to the acre. A marked ex- 

 ception, however, occurs in the case of the hairy vetch, as 

 shown in the table, where it is credited, on the basis of re- 

 peated experiments, with a tolerance of nearly 70,000 pounds. 

 This amount was attained, however, in rather sandy soils. 

 Probably some of the Algerian vetches will likewise prove 

 more resistant than those which are natives of humid climates. 



Mustard Family. As in the case of the legumes, wild plants 

 of the mustard family are rare on alkali lands ; and correspond- 

 ingly, the cultivated mustard, kale, rape, etc., fail even on land 

 quite weak in alkali. Their limit of tolerance seems to lie near 

 4,000 to 5,000 pounds per acre even of white salts. Hence 

 turnips and radishes do not flourish on alkali lands. 



Sunflower Family. Several of the hardiest of the native 

 '" alkali weeds " belong to the sunflower family, and the com- 

 mon wild sunflowers (Hclianthus calif ornicus and H. annuus') 

 are common on lands pretty strongly alkaline. The cultivated 

 Russian sunflower, as the table shows, resists the effects of 

 nearly 60,000 pounds of total alkali, of which 52,640 pounds 

 was sulfate (Glauber's salt), and 5440 common salt. This, it 

 will be seen, is a very high tolerance, so that this sunflower, 

 yielding such excellent poultry feed, is very widely available 

 Correspondingly, the ' Jerusalem artichoke," itself a sun- 

 flower, is among the available crops on moderately strong 

 alkali soils ; and so, doubtless, are other members of the same 



