c; V>. I. n.— 30 

 B. P. I.— its. .. I . 1. ■ .— ^" 



SILKWOint FOOD PLANTS: CULTIVATION AND 



I'ROl'ACJATION. 



INTRODUCTION. 



There is a small family of plants closely allied to each other, a few 

 of which supply the silkworm with food. This family is called 

 Horaces. There are three o-enera of trees in the oroup— J/"(>?v6s% the 

 mulberry (Pis. I, II, III, IV, V, and VII); To,'i/Ion, the Osac,re oran^^e 

 (PI. VIII), and Broussonetm, the paper mulhorry (PI. VI). The last 

 named, bein^^ unsuitable for silkworm food, will not aj^ain be referred 



to here. 



The Osage orang-e provides palatal)le food for the silkworm, and if 

 the worms were free to select the leaves for themselves the tree would 

 be satisfactory; but the leaves are selected for them often with bad 

 results, for the young and immature leaves have a tendency to sicken 

 the worms. Ignorance of this fact renders the use of the Osage 



orange dangerous. 



Of the mulberry there are many so-called species and a great many 

 varieties, but there are only one or two species and a few varieties 

 which are of importance in silkworm propagation. Chief among 

 these for producing silkworm food is the white mulberry, Ilorus alia 

 (PI. I). This is thought by some to be a native of China. It has 

 long been known that the white mulberry and its varieties are hardy 

 over a large area of the United States. 



The uninitiated should not be left to their own devices in growing 

 mulberrv trees, especially if the enterprise is to be an extensive one, 

 for if failure results, silkworm propagation in the particular section 

 of the country where the experiment is conducted will receive a seri- 

 ous setback. 



It is not the purpose of this paper to discuss the question of the 

 most suitable varieties of the white mulberry, as this could only be 

 done from a European point of view. Bureau, in his monograph, 

 describes 27 varieties of the white mulberry alone. In Italy, silk- 

 worm growers favor Iforus alba, variety moretti, and forms raised 

 from it. France and Spain have each its favorite kinds. Japan has 



7 



