THIRTEENTH ANNUAL YEAR BOOK— PART XII 681 



Good yields may be expected for a number of years when the blue 

 grass is kept out, especially if the soil was in good physical condition 

 and fertile when the plot was seeded. It will be observed that plot A6, 

 which was left in alfalfa for six years, maintained its yielding power to 

 the very last. It produced an average of over 4% tons per acre for the 

 five years for which the records are available. 



Plot D9, which was in alfalfa for three years produced better than 

 five tons each year, while plot 13 produced over six tons in a single 

 year and plot 14 nearly T^A tons with an average for two seasons of 5% 

 tons per acre. 



The lowest acre yield secured from any one plot in a season was from 

 plot 15 in 1905 when the yield was 2.86 tons. Even this yield however ia 

 better than is secured, except under unusual conditions, from any of our 

 other tame hays. 



SELECTION AND TREATMENT OF THE ALFALFA SOIL 



On one hundred and twenty-eight men representing all manner of soil 

 types, who reported to the Iowa Agricultural Experiment station their 

 method of seeding and handling the alfalfa crop, 85.5 per cent were suc- 

 cessful. This evidence tends to strengthen our belief that, provided 

 proper methods are used in preparing the soil to grow this crop, it can 

 be grown successfully on at least portions of practically every farm in 

 Iowa, though no doubt there are particular soils and locations which are 

 better adapted to its growth than others. 



CHOICE OF SOILS 



In selecting the soil or field whJch is to be seeded to alfalfa there 

 are several conditions which must be considered. They are: 



1. The Texture of the Soil. 



2. The Drainage of the Soil. 



3. The Fertility of the Soil. 



4. The Need of Inoculation. 



5. The Need of Lime. 



The successful growing of alfalfa or any other legume may be impossible 

 if any one of these factors is overlooked. Many Iowa soils are open and 

 Iriabie, well drained and fertile, contain the necessary bacteria and do 

 not need lime, and they may grow alfalfa very successfully merely by 

 applying good cultural methods. Most Iowa soils, however, will give 

 much better results when available fertility is supplied in the form of ma- 

 nure. Others may be ideal for alfalfa save in that they require the ad- 

 dition of the necessary bacteria; while others, particularly in south cen- 

 tral and north central Iowa, need lime. The only safe plan is to insure 

 the presence of the conditions necessary by supplying them. The crop 

 will far more than repay the trouble. 



TEXTURE OF SOIL 



Alfalfa gives much the best results on deep, loose, open, friable soils, 

 such as are represented by the loess areas along the Missouri and Miss- 

 issippi. On these soils there is practically no trouble in getting a stand 



