31 



Analyses of parts of the tobacco plant at different stages of growth 



were made at the Virginia Station in 1 894. ' Nearly One-half of the 

 ash of young plants consisted of potash, amounting to three times the 

 content of lime. The percentage of ash in the leaf at four different 

 stages was about the same, increasing slightly from topping until cured. 

 The nitrogen content was nearly 1 per cent higher at the time of top- 

 ping than when the leaf was (aired, while the percentage of phosphoric- 

 acid showed very little change, being a little higher when the plants 

 wen 1 topped than when cured. The potash was highest at topping 

 and lowest when the leaf was (aired, while the reverse was true of lime. 

 Soda was found to be a little lower at topping than at any other time. 

 The percentage of magnesia, sulphuric acid, and chlorin was found 

 slightly increased in the cured state. The plants taken from the 

 plant bed contained, in an air-dried condition, nearly 3 per cent of 

 nitrogen, nearly 1 per cent of phosphoric acid, over 8 per cent of 

 potash, and about 2.5 per cent of lime. Results further show that at 

 the time of topping the whole plant contained about 3 per cent of 

 nitrogen, one-third of 1 per cent of phosphoric acid, about 4 per 

 cent of potash, and over '1 per cent of lime. At the time of cutting- 

 it contained nearly 3 per cent of nitrogen, one-third of 1 per cent of 

 phosphoric acid, and more than ?A per cent of lime 



A series of analyse- of different grades of manufacturing tobacco 

 from Virginia. West Virginia, and North Carolina were made by the 

 Virginia Station and reported about the same time as the work de- 

 scribed above. 2 The results are of interest in showing to what extent 

 the chemical composition of grades of manufacturing tobacco is subject 

 to variations. The samples analyzed were taken from the crops of 

 1890 and 1891. The question of varieties was not considered. In the 

 sun-cured tobacco the crop of 1891 in one county contained about one 

 and one-half times as much potash, nearly twice as much sulphuric 

 acid, and one-sixteenth more lime than that of 1890. High-grade 

 bright Hue-cured and low-grade bright flue-cured tobacco grown in dif- 

 ferent counties in different years were found to contain about the same 

 amount of ash. but the low-grade tobacco contained about twice as 

 much nitrogen, phosphoric acid, potash, magnesia, and sulphuric acid 

 as the high grade. The chlorin content of the grades was about the 

 same, but the amount of soda and insoluble matter in the high grade 

 was about six times as much as in the low grade. In one county the 

 potash in the crop of 1891 was about one and one-half times that of 

 1890, the magnesia and chlorin nearly twice as much, and the insoluble 

 matter about one-fifth as much. The analyses of manufacturing to- 

 bacco grown iii Virginia agreed very well in their ash content, except 

 in one county, where it was much lower. The potash did not agree 



Virginia Station Bui. No. 50. *Ibid.,No. 51. 



