42 THE BOOK OF EVERGREENS. 



soon learn very many little ideas in connection with the 

 business which cannot be found in books. Application 

 and energy are the most valuable assistants, and with 

 these he will soon become expert. 



LAYERS. As this method is so seldom practised on ev- 

 ergreens, excepting to increase the dwarf, trailing species, 

 or an occasional limb on the taller kinds, it is not neces- 

 sary to devote much space to its discussion. The usual 

 mode of layering deciduous plants is also practised on 

 these ; and as an additional inducement to cause the forma- 

 tion of roots, we would advise, a slight covering of ever- 

 green branches as a protection from the sun, and to pre- 

 vent a too sudden evaporation of moisture from the soil. 

 A sudden twist will answer the purpose of checking the sap 

 much better than the usual method of tonguing. As a 

 rule, most plants with variegated leaves are difficult to 

 strike from cuttings, so that we are obliged to resort to 

 other modes. In such cases pots or boxes may be elevat- 

 ed to a level with the branches that we desire to operate 

 on, and the young shoots be layered in them, bearing in 

 mind that they will frequently require attention to prevent 

 the soil from becoming too dry. A protection must al- 

 ways be given them, as mentioned above. 



GRAFTING. As a means of reproduction among ever- 

 greens, grafting is the most difficult and least certain plan 

 in use. In the moist, even temperature of France and 

 England, it is prosecuted with great success ; but our va- 

 riable climate prohibits the use of it to any great extent. 

 Under glass, where the temperature can be regulated to 

 suit the operation, grafting, in some cases, is expedient. 



It should always be borne in mind when selecting 

 stocks, that some species in a genus are more closely related 

 than are others. For instance, the pines are generally di- 

 vided into groups, and each group has particular charac- 

 teristics, or idiosyncracies, that bind them together. 



Taking the White Pine (P. Strobus) as an illustration, 



