144 IOWA DEPARTMENT OF AGRICULTURE. 



cooler as that it is changing towards the opposite extreme. Every table of 

 extremes and means is a prophecy of what may be expected in future years. 

 The constants of temperature, humidity, atmospheric pressure and precipi- 

 tation appertain as much to the realty of this state as the soil and nether 

 deposits of clay, rock and coal. In fact, it is much easier for man to ex- 

 haust these resources of soil and mineral deposits than to cause even the 

 slightest change in its climatic features. 



iowa's soil products. 



Iowa's primacy in agriculture is attested by the following statistical 

 tables, compiled from the annual reports of the state Weather and Crop 

 Service for the past thirteen years— 1890 to 1902. The first table in the 

 series of crop statistics gives the average yield per acre for each year of the 

 period, and the average amount of rainfall for the state in the four critical 

 months of the crop season, May 1st to'September 1st. The second table 

 shows the totals of the staple crops for the state, and the third gives the 

 average farm price of the several products on December 1st in each year of 

 record, with the aggregate value of all soil products. In these figures as to 

 value of crops no account is made of the increment gained by feeding grain 

 and hay to farm animals. The price of corn, oats and hay on December 1st 

 is usually much less than the maximum prices for the year, and much less 

 than the sum usually realized by consuming these crops in the manufacture 

 of beef, pork, mutton, dairy and poultry products, etc. In very many 

 seasons the feeding value of corn has been double the price oflPered in 

 December, and in all years the sums actually realized have greatly exceeded 

 the farm prices current at close of the harvest. 



Corn is foremost, with an average yearly output of 261,200,756 bushels^ 

 and an aggregate of 3,395,609,836 bushels in the thirteen year period. The 

 average selling value on the farms, December 1st, has been nearly $70,000,000 

 yearly. The highest total value for a year's product was $113,000,000 in 

 December, 1901, and the lowest was $36,000,000 in 1894. In four seasons 

 during the period the corn yield has amounted to more than 300,000,000 

 bushels, viz, in 1891, 1896, 1899 and 1900. In the latter year the product 

 was 345,000,000 bushels, which is the maximum amount for all the years of 

 record, according to the figures compiled by the state crop service. The 

 United States census of 1900, however, credited this state with a total of 

 383,453,190 in the year 1899, produced on an acreage of 9,804,076 acres. 

 The census figures are of value as evidence that the statistics of the Iowa 

 crop service have been made on a conservative basis as to acreage and aver- 

 age yield. For the past fifteen years the total corn output of Iowa has ex- 

 ceeded any other state in this country, or any other country. Other states 

 have grown more bushels per acre on very small areas; but Iowa is in the 

 lead because it possesses the largest area of farm lands adapted to the pro- 

 duction of this great staple. By rotation of crops, it has been possible to 

 produce corn continually on about one-fourth of the area in farms, without 

 exhausting the soil. 



The average annual yield of corn has been 31.5 per acre for the state at 

 large. During the past decade the yield per acre has averaged about two 

 bushels higher than in any previous ten-year period; as a result of improved 

 methods in selection and care of seed, preparation of seed bed and cultiva- 

 tion of the crop. The highest yield per acre for the state was harvested in. 



