ROTATION AND CULTURAL METHODS AT EDGELEY, N. DAK. 3 



PRECIPITATION. 



The average annual precipitation at Edgeley for the 19 years from 

 1901 to 1919, inclusive, was 18.02 inches. The highest was 28.61 

 inches, in 1902, and the lowest 10.85 inches, in 1917. The highest 

 precipitation recorded in any one year since the experiments began 

 was 22.20 inches, in 1915. 



The average precipitation by months is : January, 0.28 ; February, 

 0.33; March, 0.87; April, 1.92; May, 2.71; June, 3.38; July, 2.80; 

 August, 2.27; September, 1.70; October, 1.01; November, 0.34; and 

 December, 0.41. 



The average seasonal precipitation for the five months of April, 

 May, June, July, and August is 13.08 inches, or 72.5 per cent of the 

 total annual precipitation. 



EXTENT OF WORK AND CHARACTER OF THE SEASONS. 2 



In the 14 years from 1906 to 1919, inclusive, the following number 

 of plat records have become available : Wheat, 485 ; oats, 415 ; barley, 

 123 ; corn, 505 ; flax, 14 ; alfalfa, 39 ; brome-grass, 52 ; red clover, 26 ; 

 green manure, 98; fallow, 230; total, 1,987. Of this total number, 

 1,559 have been crop plats and 328 green-manure and fallow plats. 



The average yields each year from all plats in the main field are 

 shown in Table I. For wheat, oats, barley, and corn these averages 

 are from a considerable number of plats, embracing a wfde range 

 of methods. They therefore give a fairly good indication of the 

 effect of the season on yields and of the yields that may be expected 

 with a wide range of methods, such as are likely to be practiced by 

 farmers. The vital question, of course, is how much these averages 

 may be increased or the poor years overcome by the choice of 

 methods. This will be considered in its proper place. 



The flax yield specified is not a fair showing for the flax crop, as 

 it is from a single plat on brome-grass sod. The brome-grass yield 

 is the average of two 1-year-old plats and two 2-year-old plats. The 

 alfalfa yield is the average of one 1 -year-old and one 2-year-old plat. 

 The red-clover yield is from one plat in the second year after seeding. 



The year 1906 was a good one, with some lodging and some rust. 



2 Since this manuscript was prepared the 1920 crop results have become available. 

 In the main field the average yields were : Wheat, 9.6 bushels ; oats, 47.3 bushels ; 

 barley, 25.4 bushels ; brome-grass, 2,075 pounds of hay ; corn, 2,383 pounds of fodder ; 

 and the flax, alfalfa, and red clover were failures. The wheat crop was damaged by 

 rust,, lodging, and weeds. The" damage was generally greatest and yields the lowest on 

 those plats that had the greatest growth of straw and a,t one stage of growth the 

 highest potential yield. Drought and hot weather after early grain harvest prevented 

 the corn from earing. Flax was destroyed by wilt and dry weather. With all grain 

 crops, disked corn ground produced the heaviest or one of the heaviest yields. Yields 

 on fallow were especially poor for wheat and below the average for oats and barley. 

 The data make no decisive contribution to tbe knowledge of the effect of manures. 



