REGENERATION BY MEANS OF CULMS. 389 



fittrvive beyond the sapling stage ; and (2) suckers can be relied 

 upon to rapidly fill up an open forest. 



In the second place, suckers are practically independent stems 

 from the moment they make their appearance. 



In the thinl place, suckers, owing to their very origin, come up 

 perfectly straight from under the ground itself, and being free 

 to develop equally on every side, form concentric rings of uniform 

 thickness throughout, and thus continue to grow up straight ; 

 whereas a stool-shoot, unless it originates from an adventitious bud 

 (a comparatively rare contingency), or is the result of underground 

 exploitation, necessarily starts horizontally and describes a more or 

 less broad curve in assuming a vertical position, and then the 

 parallel growth of its sister-shoots, and especially the presence, on 

 one side, of the parent stool, compels its roots to spread out in only 

 a single direction outwards, so that the strong curve at the base of 

 the stem is maintained almost as long as the tree lives, and the 

 irregular structure of the wood renders several feet of the thickest 

 part of the bole unfit for sawing. 



In the fourth place, stool-shoots, unless they spring up on very 

 small stools (not more than a few inches in diameter), are almost 

 always unsound at the base ; whereas trees originating as suckers 

 are, like seedlings, generally sound right down to the crown of the 

 roots. 



In the fifth place, trees nearly always retain the power of pro- 

 ducing suckers much beyond the age at which they cease to be able 

 to grow up again from the stool. 



In the sixth place, as suckers can come up during the existence 

 of the parent tree, which can furnish them with nearly all the 

 nourishment they need, they require less illumination to form 

 and grow up than stool-shoots, and are therefore less affected 

 by the presence of stores, which may themselves be the parents of 

 the suckers. 



We thus see that, provided they belong to economically or 

 culturally valuable species, suckers are nearly always more desi- 

 rable than stool-shoots. 



SECTION IV. 

 Regeneration by means of culms. 



Amongst woody species this method of regeneration is possible 

 only with bamboos. Before rules for work can 1 o laid down it is 

 necessary to study the peculiar mode of growth of bamboos in 

 general. 



