SOYBEANS FOR .MASSACHUSETTS 7 



such that good tihh is easil\- maintained. Ft can be worked sofjn after a rain 

 without fear of puddling. Altogether, the soil used nia>' be considered as almost 

 ideal for soybeans. 



The soybean plots were rotated on the experimental field. Areas which had 

 received no fertilizer within recent years received 600 pounds of 16 per cent 

 superphosphate and 300 pounds of muriate of potash per acre. This treatment 

 was reduced one-third in amount when the area used for soybeans had been 

 fertilized within recent \ears for other crops. No nitrogenous fertilizer was used 

 for soybeans. The seed were inoculated with symbiotic bacterial cultm"es just 

 prior to planting. 



There was more or less infestation of downy mildew (Ferouospora sojae Wolf) 

 and bacterial leaf spot {Bacterium sojae) during the period of the test. In 1^)31 

 grasshoppers caused some damage, and in 1932 the Mexican bean beetles slightly 

 damaged the crop. 



The mean annual rainfall at Amherst is 43.49 inches, and for Ma\', June, Juh', 

 August, and September 19.53 inches. This is usualK- fairK- evenly distributed 

 throughout the growing season, the mean \ar\ing from 3.5 to 4.3 inches per 

 month. The total precipitation for the fi\"e months indicated abo\'e for the 

 period under consideration was as follows: 



\ ear Inches 



1929 13.09 



' 1930 16.21 



1931 24.62 



1932 14.75 



A se\'ere drought occurred during Jul\' and August in 1929, when the total pre- 

 cipitation for these two months was onl\- 2.24 inches. Crops on light, well- 

 drained soils of low water-holding capacity in this vicinit\' suffered from shortage 

 of water; but owing to the great depth and water-holding capacitx' of the soil 

 used for this experiment, and probabh" to a certain amount of water seepage 

 from higher levels, the soybeans did not suffer much, if an\'. 



The mean date of the last frost is May 12, and of the first frost September 19, 

 in Amherst. Thus the mean length of the growing season for tender crops is 

 130 days. Planting usualh' occurred about the first of June, and the crop was 

 harvested from about the last week in August to the second week in September. 

 Ample time seems to have been available for production of maximum tonnage 

 of forage of the varieties tested. There is little if any advantage in planting 

 before the first of June, from the stamlpoint of forage production. 



Production Data 



In Table 1 are given field notes and data obtained on the varieties tested 

 in 1929. Data such as these will \ar\' more or less from year to \ear. but they 

 will be of approximately the same relative order. 



In Table 2 are gixen the >ield of soybean seed for 1929 and 1930, the onl\- 

 years for which seed yields were taken, and the ha\- fields for the period 1929- 

 1931, inclusive. A study of this table shows that 1929 was on the whole a better 

 year for seed than 1930, whereas forage production was better in 1930. July of 

 1929 was abnormally dry and may have permitted better pollination than occurred 

 in 1930 when the rainfall was slightly above normal. The }ield of forage may 

 have been converseK- affected for the same reason. 



