82 EXPERIMENT STATION. [Jan. 



On the basis of the above figures, the stalks on an acre would 

 contain the following amounts of plant food : — 



Nitrogen, 87.23 



Potash, 132.85 



Phosphoric acid, 20.94 



Applying the same commercial values that are usually given 

 to the plant food found in cottonseed meal, castor pomace and 

 other organic vegetable substances, the total value of the stalks 

 per acre would be about $24, or about $8.40 per ton of partially 

 dried stalks.-^ If this same valuation is applied to the total 

 product of the State, the commercial value of the plant food 

 found in the tobacco stalks grown in ]\Iassachusetts for the year 

 1912 amounts to $136,800.- 



The usual method of handling tobacco stalks is as follows: 

 the stalks from which the leaf has been stripped are thrown out 

 upon the land during the fall and allowed to remain until 

 spring, thus permitting the rains and snows to dissolve any 

 valuable fertilizing material which the stalks may contain. 

 They are then placed in small piles, burned and the ashes scat- 

 tered over the adjoining land. If all of the plant food were 

 washed out of the stalks by leaving them thus exposed, this 

 perhaps would be an economical manner of disposing of the 

 material, but even then there would be the loss of a large amount 

 of organic matter which eventually would have furnished 

 humus. 



The matter appeared to be of sufficient importance to warrant 

 a few chemical tests to see to what extent the plant food was 

 removed by the exposure of the stalks upon the land during 

 the fall and winter months. Stalks thus exposed were procured 

 under average conditions and subjected to a chemical analysis 

 with the following results (calculated to a dry-matter basis) : — 



1 By "partially dried" is meant a material containing 50 to 53 per cent, moisture; the green 

 stalks at stripping time may contain from 70 to 75 per cent, moisture. 



- This valuation is somewhat high for the reason that the labor cost of handling a definite 

 amount of plant food in tobacco stalks would be greater than that of handling the same plant 

 food in cottonseed meal. 



