SUGAR BEETS: PBEVENTABLE LOSSES IN CULTURE. 9 



namely: (1) Those occurring in the germination stand prior to thin- 

 ning: (2) careless and improper thinning and blocking; and (3) 

 those incidental to cultural operations between thinning and harvest. 1 



SOURCES OF LOSS IN THE GERMLNATTON STAND. 



The sources of loss found between the time of sowing and the dual 

 operation of spacing and thinning are (1) poor preparation of the 

 seed bed ; (2) imperfect operation of seed drills ; (3) late frosts ; (4) the 

 damping-off disease; (5) the blowing of light, sandy soils; (6) flea 

 beetles; and (7) cutworms or wireworms. 



LOSSES IN STAND FROM THINNING. 



Improper thinning was found to be the greatest single source of 

 loss in stand, the more serious because nearly imperceptible and unsus- 

 pected. This loss is caused by the double operation of blocking and 

 thinning. It is one of the most costly operations in the cultivation 

 of sugar beets and, strange to say, the one most frequently intrusted 

 to hired labor or contract work. Worse still, it is seldom efficiently 

 supervised. Invariably the space left between the plants is greater 

 than the farmer imagines or intends. When the plants have attained 

 a moderate size, it is almost impossible to distinguish, without count- 

 ing, between stands of 50, 60, or 80 per cent. 



LOSSES IN THE HARVEST STAND. 



The difference in the percentage of stand between that shown imme- 

 diately after thinning and that existing at harvest time is to be 

 attributed to inefficiency in the cultural operations during the inter- 

 vening period. Some of these losses are caused by the eradication of 

 plants with the hand hoe and their destruction by the hoofs of horses 

 or by implements, especially when turning at the ends of rows, and 

 by poor guidance of the cultivator, whereby it swerves and cuts out 

 the plants along the rows. (In this way from one to four rows may be 

 damaged at each round, according to the type of cultivator employed.) 

 The flooding of low areas and the drying out of high ones, as well as 

 cutting through rows to distribute water in poorly graded fields, are 

 additional sources of loss. (See Table II.) 



It soon became apparent that the observations could most profit- 

 ably be confined to a determination of the nature and extent of losses 

 in stand and their causes. From these data it appeared possible to 

 discover whether correlations exist between such losses and the yield 

 of the respective plats. 



To ascertain the percentage of the stands throughout the season, 

 measurements were made of the actual distance between all the plants 

 in every row under observation, instead of obtaining merely the aver- 



1 Germination stand is the stand of beets resulting from the germination of the seed up to the time of 

 t hinn ing. Thinning stand is the stand or number of plants left after blocking and thinning. Harvest 

 stand is the number of beets to the acre at harvest time. 



91241°— Bull. 238—15 2 



