MULBERRY-DWARF TROUBLES IN JAPAN. 209 



Absolute quantities in the root-bark of one stock. 





Takasuke. 



Tsurula. 



fumonji. 





(May 18.) 



(May 28.) 



(May 28.) 



Dry matter in the. hark of roots... 



341 grams 



293 



38.2 



Total nitrogen 



5.900 



4.020 



4-930 



Albuminoid nitrogen 



3.820 



2.780 



3-630 



Non-albuminoid nitrogen .. 



2.080 



1.240 



1.300 



Although the above are only approximate values yet there 

 will be no great error in assuming that nearly 4-6 grams nitrogen 

 is still contained in the roots after cutting ; but this quantity of 

 nitrogen is not entirely available for the young shoots, because a 

 portion of it is in the form of insoluble compounds, and only a 

 portion is capable of being transported to the growing parts. If 

 we assume the quantity of non-albuminoid nitrogen as represent- 

 ing the quantity of available nitrogen, there will be no great 

 error ; and in that case 1.3-2.0 grams or at most 3 grams can 

 be utilized by the new developing shoots. Let us now see wheth- 

 er this quantity is sufficient for the energetic development of 

 the new shoots. 



On July 11, when the new shoots had reached the height of 

 4C-60 cm., they were analyzed, and the following results were 



obtained : 



0 Takasuke. 



Total dry Nitrogen Sum total ot 



matter. in same. nitrogen. 



New stems .19.6 O.337 o oco 



T rr a 3.262 g. 



Leaves. ..55.4 2 -925 



2) Tsuruta. 



New stems 50.4 0.842 ^ gg 



Leaves 92.1 4.817 



3) Jumonji. 



New stems. 28.4 0.585 3 



Leaves ...50.0 2.620 



We see now that when the young shoots had reached the 



height of about 50 cm and the dry matter of the leaves amount- 

 ed to about 50 gram?, there were more than 3 grams of nitrogen 



