Arizona Agricultural Experiment Station. 164 



loam, and irrigated at once, as is necessary at this time of year. 

 The winter being quite mild, a fair growth was made. Samples 

 taken April 2 gave the following results: Average weight oi beets 

 dug, 12.0 ounces; yield per acre, 11. 5 tons; sugar in beets, 14.7 

 per cent; purity .co-efficient, 83.3 per cent. These are probably 

 as good results as could ordinarily be expected from seed sown on 

 the earliest practicable autumn date. 



At the close of the year 1899 bulletin 31 was issued giving 

 the result of the year's work. The averages from ten plats sown 

 during January and February, 1899, were as follows: Yield per 

 acre, 9.75 tons; per cent sugar in beets, 15.0; purity, 77,7; avail- 

 able sugar per acre, 2010 pounds. The most important of the 

 conclusions from the work of the year was that winter-sown beets 

 are not benefited, and may be injured, by early irrigation, pro- 

 vided the soil has been thoroughly irrigated previous to seeding. 

 The indications were that the most advantageous time to begin 

 irrigating is when the beets are two to three months old. 



A plat sown December 26 and first irrigated April 1 gave the 

 following results: 



June 15. 



July 1 . 



July 11 



July 30 



The yield upon the latter date was 14.5 tons per acre, giving 

 an approximate yield of available sugar per acre of 4050 pounds, 

 the highest yield yet obtained from any of the experimental plats 

 during the past four years. This yield of sugar per acre evidently 

 remained about constant during all of June and July, the increase 

 in the percentage of sugar being just about counterbalanced by a 

 decrease in the purity coefficient. Only a tenth of an inch of rain 

 fell upon the plat from the time of seeding until the first irriga- 

 tion over three months later, during which period they made an 

 excellent growth. This result was accomplished by a thorough 

 irrigation of the soil previous to seeding. 



A plat sown January 23 and first irrigated April 3 gave the 

 following results: 



