EFFECTS OF FKOST UPON SORGHUM. 



157 



The effects of these frosts were far more disastrous upon the first 

 group of sorghums selected, than upon the last group ; for, arranging 

 the results side by side, this difference in effect produced is readily 

 compared, thus : 



Sucrose percent 



Glucose do.. . 



Solids do 



Juice do 



Specific gravity 



Available sugiir per cent 



First Group. 



Loss 44 1 



Gain 26 S 



Loss ]5 9 



Gain 6 



T.oss 30 9 



Loss 69.8 



Second Group. 



Gain • 2 9 



Gain 22 5 



Gain 51 .4 



Gain 2.3 



Gain .t 1 



Loss 12 1 



As will be seen from the above statement, there is practically little 

 effect shown by the frost upon the several varieties of sorghum in the 

 second group. The percentage of increase in glucose and solids is, in 

 fact, not a very large actual increase, while the percentage of sucrose 

 in the juice is slightly more. 



It is more than probable that the difference in the effects of the frost 

 upon the two groups is due to the fact, that, in the case of the second 

 group, the different varieties of sorghum were those of early maturity, 

 and this will be seen by reference to the tables of analyses of these 

 varieties, which will show that for a long period these varieties had 

 reached their maximum content of sugar, and, in fact, had begun to 

 fall off a little ; Avhile, as will be seen by reference to the tables, the 

 members of the first group were of the late varieties, and their full 

 development had not yet been attained, for their content of sucrose 

 was and had been gradually increasing. It is, therefore, probable 

 that, while the plant is in its immature condition, and the functions of 

 growth and the elaboration of its sugar in vigorous action, it is far 

 more susceptible to the action of frost than after full maturity has been 

 attained. Should this prove to be the case, it would explain the inju- 

 rious action of frost upon the sugar cane of Louisiana, which, owing 

 to the long period necessary for its full development, can never reacli 

 that condition of maturity Avhich would render it comparatively safe. 



The above results will enable us to explain the very conflicting tes- 

 timony of sorghum growers as to the effects of frost upon their crops, 

 many having experienced no evil results, while others have found the 

 effects of frost most disastrous. At least these results will be of value 

 in guarding us from drawing too hasty conclusions, .«ince a reasonable 

 support is afforded in the above data for either view, and it would seem 

 wise to withhold conclusions until more facts are accumulated. 



In 1882, however, as has been already pointed out, the meteorolog- 



