SHRUBS AND TREES. 119 



which have the strength, or the thorns, to prevent animals from 

 going through them, we know of none that have been proved. 

 What is called the Evergreen thorn, Crategus pyracanthus, is an 

 admirable thorny hedge-tree, but not truly an evergreen. It may, 

 perhaps, rank as a sub-evergreen. The Menzies fir, Abies men- 

 ziesii, seems to be peculiarly fitted for such a hedge, its leaves 

 being sharp and stiff as needles, the growth compact, the foliage 

 dense, and pointing in all directions. It is now a high-priced tree. 

 When it becomes cheap we hope to see it tried for hedges. Like 

 the hemlock and the balsam fir, it does best in a warnij humid soil, 

 and it is possible that in the exposures required for hedges, it may 

 not prove hardy enough to resist both the sun and: the cold. The 

 Cephalonia fir, Pieea cephalonica, though its leaves are less 

 cutting than those of the Menzies fir, are still somewhat formida- 

 ble ; and as its growth is vigorous, healthy, and compact, it may 

 prove valuable for large hedges. 



There are some dwarf species of white pine which will make 

 exquisite low hedges of a broader and rounder form than is recom- 

 mended for any of the foregoing trees ; but they are not yet fur- 

 nished at such rates as to make their use practicable ; and the 

 common white pine may be clipped into hedge forms. 



The American holly, Ilex opaca, has stiff glossy leaves armed 

 with spines on their scolloped edges, and will probably make the 

 most formidable of evergreen hedges for this country. 



The yews, much employed in England for hedges, are not hardy 

 enough to be used north of Philadelphia. 



Among deciduous trees and shrubs the number adapted to 

 hedges is much larger than most persons suppose. Almost the 

 whole family of thorns, natives of this country, as well as of 

 Europe, besides the fragrant hawthorn, are easily made into excel- 

 lent hedges. Our wild crab-apple tree can be trimmed into a 

 compact form of superlative beauty and fragrance in the blooming 

 season, and sufficiently offensive by its thorns to turn trespassers. 

 The mere capability of any tree or shrub to become a strong, 

 dense, and handsome wall of foliage, if kept down to a hedge 

 form, is not a sufficient recommendation. It is not so much a 

 question of what trees and shrubs can be made into hedges, as 



