ILLUSTRATED GUIDE. 



43 



kinds, pointing out, however, where necessary, any dif- 

 ference in their treatment. Cool, sandy soils best suit 

 the birch. As its roots do not descend far, it does not 

 require deep land. Its sap, which is abundant 

 in spring, contains about one per cent of\ 

 sugar. The seed ripens in autumn, and may 

 be sown either then or in spring ; but as it is 

 rarely ripe before Noyember, it is generally 

 -necessary to wait till the latter season before entrust- 

 ing it to the ground. If the seed is buried in damp 

 sand, and kept in a cool place, it will preserve its 

 germinating power for six months. A pound of this 

 contains about four hundred thousand seeds, not more 



13, — Butula lenta — Black-birch — Branch, 

 leaves and seed-Dod. 



than twenty per cent of which will grow ; it should, 

 therefore, be sown very thickly, on land in a roughish 

 state, and only covered slightly by a pressure of the 

 foot. If every thing goes well, the young plants will 

 appear above ground in a month, and at the end of 

 a year from sowing, they will have attained a height of 



