MEDICAGO FALCATA, A YELLOW-FLOWERED ALFALFA. 47 



The actual water requirement of the first, second, third, and com- 

 bined crops for each year is given in the second to fourth cokimns 

 of the table, and the relative water requirement of each crop, with 

 Medicago sativa taken as 100, is given in the last four columns of 

 Table VI. Considering the water requirement of the combined crops, 

 it will be noted that Medicago fdlcata has a slightly lower require- 

 ment than Medicago sativa. The water requirement of Medicago 

 falcata., based on data obtained from 29 separate pots which are 

 summarized in the table, is 663dzl5, and the water requirement of 

 Medicago sativa, as determined from 25 separate pots, is TlSztlS, or 

 a difference of 50 ±23 in favor of Medicago falcata. This difference, 

 in view of the large probable error, which was in part due to varia- 

 tion in season and location, is not significant. It would appear from 

 the above data that Medica.go falcata is relatively efficient in its use 

 of wat€r during the early part of the season, but inefficient during 

 the late summer. 



There is little doubt that the drought resistance of Medicago fal- 

 cata is quite as high as that of Medicago sativa., but it is unlikely that 

 the former can be grown profitably where the latter succumbs. There 

 is a vast agronomic difference between being able to maintain an 

 existence under extremely dry conditions and being able to produce 

 sufficient growth to be profitably utilized for hay or pasture. There 

 is certainly no definite evidence that Medicago falcata will be profit- 

 able where the better adapted strains of Medicago sativa fail. 



SEED PRODUCTION. 



The seeding habits of Medicago falcata are such as to give serious 

 concern in connection with its utilization as a cultivated forage crop. 

 Not only is the quantity of seed produced comparatively small, but 

 a large percentage shatters before it can be harvested by ordinary 

 methods. Even in harvesting by hand the loss of seed through 

 shattering is great. There are no data available on yields of seed 

 under field conditions, but there are numerous data on yields from 

 individual plants, from which estimates can be made of the yields 

 which might reasonably be expected under field conditions. 



At Brookings, yields from a large number of plants were recorded 

 from 1010 to 1918, inclusive. The plants were grown in hills 24 by 36 

 inches, thus providing what are generally considered very satisfac- 

 tory cornlitions for seed production. Special care was exercised in 

 harvesting the seed to reduce the shattering to a minimum. There- 

 fore the yield was apprecial)ly greater than if the i>hints had been 

 harvested by ordinary field rn(!thods, and was high also for a fair 

 coinpari.son with Medicago sativa. 



