BULLETIN 1304, U. S. DEPARTMENT OF AGRICULTURE 
Three seasons having almost identical precipitations produced 
widely varying yields of the same crops, indicating a wide variation 
in the effectiveness of a given amount of precipitation. The effective- 
ness of the precipitation is dependent on how it is distributed over the 
growing season and by the extent to which it is supplemented by water 
in the soil at the beginning of the season. 
The average seasonal precipitation from April 1 to September 30, 
inclusive, was 13.69 inches for the 16-year period under consideration. 
The seasonal precipitation was greater than this eight times and less 
eight times. The seasonal precipitation is 76 per cent, or about 
three-fourths, of the annual precipitation. The percentage of the 
seasonal of the total precipitation for each year varied from 61 per 
cent in 1913 to 94 per cent in 1910. Four tunes the percentage was 
below 70, eight times it was between 70 and 80, and four times it was 
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Fig. 1.— Average monthly precipitation at the Akron Field Station for the 16 years from 1908 to 1923, 
inclusive 
above 80. The highest seasonal precipitation recorded was 19.44 
inches, in 1915, and the lowest 9.15 inches, in 1921. 
The average precipitation for the other six months of the year 
was 4.26 inches. The highest precipitation in any one six-month 
period from October to March, inclusive, was 9.64 inches, iti 1908-09, 
and the lowest 1.59 inches, in 1910-11. The winter precipitation 
was less than 4 inches six times and greater than 4 inches nine times, 
but it exceeded 5 inches only three times. As a general rule, much of 
the winter precipitation is lost so far as crop production is concerned, 
as it usually occurs as snow accompanied by wind, which drives it off 
the open fields and piles it up in drifts. The more that farm prac- 
tices or methods contribute to catching and conserving this winter 
precipitation falling as snow, the greater the advantage to the fol- 
lowing crop yield. 
The average monthly precipitation is shown in Figure 1. 
