DISEASES OF THE MULBERRY ] 163 



the labourers are picking the leaves of the mulberry. 

 For this reason it will be necessary to sow only the 

 open spaces between the rows of trees, leaving the 

 rest for other cultivation. Crops which are lifted or 

 harvested before the time when the feeding season 

 of the silkworm is in full swing such as potatoes, green 

 forages, winter vegetables, vetches etc. of course are 

 not exposed to this drawback; and on irrigated lands 

 summer vegetables can be grown without much trouble. 

 An adult middle-sized tree produces on an average 

 10 kilog. of foliage, and as according to the best 

 authorities, from 18 to 25 kilog. of foliage are required 

 to produce j kilog. of cocoons, it follows that in order 

 to produce 1000 kilog. of cocoons (one metric ton), 

 it is necessary to have at hand the foliage of 2500 

 mulberry trees of average size. Considering the question 

 from another point of view, it is generally admitted 

 that in order to feed the silkworms produced by one ounce 

 (30 grammes) of "seed" or eggs from the moment 

 that they are hatched to the formation of the cocoon, 

 from 750 to 800 kilog. of foliage will be required, 

 equivalent to the produce of about 80 adult trees of 

 average size, so that the final production of cocoons 

 per tree works at an average rate of f of a kilogram. 

 It is obvious that the production of foliage by very 

 young trees is almost negligeable. In the 4th or 5th 

 year after planting the production may be reckoned 

 at about 2 kilog. per tree. The full production is reached 

 when the tree is 25 to 30 years old, and therefore 

 large plantations of mulberries are necessary before it 

 is possible to establish the silk industry on a satisfactory 

 footing. 



DISEASES OF THE MULBERRY. 



As in the case of the fig tree, the mulberry when 

 grown on lands which are too stiff and badly drained 

 is liable to sudden death, or rather the tree falls into 



