C MA E A C TE R ISTI C S OF TREES. 



28; 



3. 73. 



The balsam fir, the Norway spruce, and Fig. 74. 

 the hemlock are conical fi-om first to last, 

 swelling out, however, at maturity, into the 

 ovate-conical form, of which the Swiss or 

 stone pine {P. cembra), Fig. 73, is a type in 

 ever}.- stage of its growth. The cedar of 

 Lebanon is a distinctly pyramidal-conical 

 tree when young, but widens out as it ma- 

 tures, and finally spreads into an immense 

 oblate head. The junipers embrace species which are the most 

 slenderly conical of evergreens : the Irish juniper, Fig. 74, having 

 rather the form of a slender club than of a cone. Some varieties 

 of the Norway spruce, and the European silver-fir, are now being 

 propagated, which have branches so pendulous that they are nearly 

 as slenderly conical as these junipers. 



Among deciduous trees the Lombardy poplar. Fig. 75, Fig. 75 

 is the type of what are called fastigiate trees ; /. e., trees /', 

 of upright and compact growth, being distinguished from 

 other conical trees by a tendency to vertical parallelism 

 of the branches. The balsam fir and the Norway spruce 

 are both conical trees, but having nearly horizontal 

 branches, are not fastigiate ; while the Irish juniper, the 

 arbor-vitces, and the Lombardy poplar, are all fastigiate. 

 It needs to be impressed on novices in the study of 

 trees that all these various types of trees vary greatly 

 among thenv^jlves, so that specimens of any species are 

 often seen quite different from the usual type of that spe- 

 cies. These variations are called varieties, and when very 

 marked in their character are named, propagated from, and be- 

 come the curiosities of arboriculture. 



Pendulous or Weeping Forms.— Of late years, such num- 

 bers of new varieties of pendulous trees have been introduced, 

 that they might perhaps be considered as a class ; but in a simple 

 classification of trees by their outlines alone, they will be found to 

 group easily with one or another of the classes already described. 

 Pendulous varieties have been found among nearly every species 



