150 MASS. EXPERIMENT STATION BULLETIN 154. 



alfalfa under the best conditions excels the clovers. Its roots 

 penetrate more deeply, and the total crop residue — root and 

 stubble — is greater. 



The Soil for Alfalfa. 



Alfalfa will thrive on soils of many different kinds, but 

 whatever the type it must satisfy certain conditions : — 



1. It should have good depth and be rich, especially in the 

 mineral elements of plant food. Medium loams, inclining 

 rather to be somewhat heavy than light, will give the best 

 crops. The soils which contain too large a proportion of clay 

 retain so much moisture that in open winters the crop, 

 especially when young, is liable to heave. 



2. Stagnant w^ater in the subsoil is highly injurious. In 

 soils with good capacity to conduct and retain water the 

 presence of standing water in the subsoil (determined by sink- 

 ing trial holes) within less than 5 or 6 feet of the surface will 

 be highly injurious. If the subsoil be free from standing water 

 to much greater depth it will be a distinct advantage. In the 

 case of soils of coarser texture, which do not conduct w^ater 

 freely in large quantities, and which have deficient capacity 

 to retain water, the water table may be nearer the surface 

 without disadvantage, but even wdth such soils it would, 

 doubtless, be inadvisable to attempt the cultivation of alfalfa 

 with standing water nearer than 4 or 5 feet below the surface. 



3. The field must have sufficient surface slope to carry off 

 water, and there must be no pockets "which will retain water. 

 In fields which are too level, or in pockets, the formation of 

 ice on the surface is fatal to alfalfa. It is, of course, possible 

 that in this climate ice may sometimes form on the surface, 

 even on considerable slopes, but this is a danger which cannot 

 be avoided, and it is least on slopes. 



4. The presence of a hardpan wdthin less than 10 or 12 feet 

 of the surface, or an excessively compact subsoil, will prove 

 unfavorable; so, also, will a shallow soil underlaid by rock. 



5. The soil must not contain free acid, though if this con- 

 dition exists at the start it can be corrected by the use of 

 lime. 



6. The richer the soil naturally is in lime the better suited 

 it is likelv to be for alfalfa. 



