16 HABIT [CH. 



" round-headed," " spreading," " erect," and so forth, vague 

 as they are, are difficult to escape. 



Similar problems beset us on examining the habit of 

 shrubs and bushes. It is very easy to select certain well- 

 marked types, such as the creeping or trailing Willows, 

 e.g. Salia; repens, and the various climbing shrubs, be 

 they Twiners like the Honeysuckle, Tendril-climbers such 

 as the Vine, Scramblers like the BlackbeiTy, or Root- 

 climbers like the Ivy ; yet the vast majority of them 

 are more or less erect, " round-headed " shrubs, only dif- 

 fering from trees in having no single and distinct stem, 

 but bearing their foliage shoots on a varying number of 

 branches that rise direct from the around or from the 

 base of one or more piiucipal stems. 



Moreover, apart from size and shape which offer us no 

 constant distinction between tree and shrub, the difficulty 

 arises that coppiced trees — i.e. trees which have been cut 

 down close to the ground and allowed to throw up several 

 branches from the stool — are in the condition of shrubs, 

 and remain so until some one of the branches takes the 

 lead and forms a new stem. The peculiar forms presented 

 by coppiced trees, moreover, are entirely artificial, as is 

 also that much more conspicuous form known as the 

 pollard. A pollard Oak or Willow in fact only differs 

 from a coppiced Oak or osier Willow in the height at 

 which the lopping of the stems and branches is performed ; 

 in the former at some feet above the surface of the soil, in 

 the latter close to the ground. 



It will be the subject of a later chapter to investigate 

 the part played by the branches in building up the form 

 of the crown, but meanwhile attention may be directed to 

 some broad features in the large class of " round-headed " 

 trees. Any observant person must have noticed that one 

 marked difference between the crown of an Oak, Plane, or 



