ELEVENTH ANNUAL YEAR BOOK— PART XI 579 



alfalfa will not thrive in soils that are sour and that there are many such 

 in the state. In some of the experiments conducted during the last few 

 years, liming has been found to increase the yields of alfalfa, while in 

 other cases the lime produced no apparent effect. 



Soils that produce good crops of clover will probably not be seriously 

 in need of liming for alfalfa. On the other hand, where there is trouble 

 in getting a stand of clover, or where this crop does not otherwise succeed 

 well, it will usually pay to lime the soil, and liming may be actually neces- 

 sary before alfalfa will do well, because the alfalfa bacteria will not thrive 

 in acid soils. 



In the case of soils that are sour because of lack of drainage, liming 

 alone will not be sufficient. Drainage must receive first attention. The 

 soil must also be otherwise put into good physical condition by proper 

 tillage methods, the addition of humus, etc. After these things have been 

 attended to, if the soil is in need of lime this substance can do its work 

 properly. 



The most satisfactory method of determining whether or not a soil is 

 in need of liming, is to make a small trial application of lime on a patch 

 sov/n with alfalfa, some time before seeding the whole field. Such an 

 experiment may result in saving the expense of liming and is well worth 

 making, where there is serious doubt, because in many instances there 

 is a sufficient natural supply of lime in the soil. In some portions of 

 the state where there is an abundance of limestone, the soils may, never- 

 theless, respond to applications of lime because they bear no direct relation 

 to the rock upon which they rest. 



Where liming is necessary, an application of ground limestone will 

 usually be most economical, although other forms of lime will give equally 

 good results. The amount that should be applied will depend upon the 

 needs of the soil, but probably not less than two tons of ground limestone 

 per acre should be used, and double this amount may be profitable. It 

 may be applied at any time but the longer before sowing the alfalfa the 

 better. It is a good plan to begin preparing the ground for alfalfa a year 

 or so in advance and in that case the lime may be applied when preparing 

 the soil for the preceding crop. If the ground for alfalfa is to be plowed 

 in the fall, the lime may be applied at that time. In spring preparation, 

 the lime should be applied immediately after plowing and disked into the 

 soil so as to give it as much time to act as possible before seeding. 



THE TIME TO SOW AEFAEFA. 



If the weather conditions are favorable and the soil is in good condition 

 and free of weed seeds, it does not seem to make any important difference 

 when the seed is sown so long as there is sufficient time for the young 

 plants to thoroughly establish themselves before winter, and good results 

 may be secured at any time from April to August. Trouble with weeds is 

 most likely to arise with the earlier seeding, while with the later seeding 

 there is liable to be an insufficient supply of moisture in the soil to permit 

 of proper soil preparation, and the germination of the seed and the develop- 

 ment of the plants may be seriously delayed by periods of drought. In the 

 experiment station's trials with late summer seeding during the last five 



