THE PLANTEK's GUIDE. 



95 



placed by the pnming-knife ; and when it came to be 

 shortened a second time, there appeared, of course, a still 

 greater multiplicity. The truth seems to be, that no phy- 

 siological obseryations as yet made are inconsistent with 

 this doctrine. Art or accident may cut off or shorten 

 either the tap-root or the pre-eminent shoots of the top, 

 but the plastic po\Yers of most trees will soon renew 

 them ; not indeed with the same degree of strength 

 individually in either, but in greater numbers, aggregately 

 qualified to perform the same functions in nourishing the 

 plant.''" 



Further, roots are materially determined in their 

 form, by the nature of the soil in which they grow ; in- 

 somuch that, in many instances, before we can pronounce 

 on their true form, we must be aware of the condition and 

 texture of the soil that is most natural to them. Their 

 deyelopment is most luxuriant in ground that is neither 

 too loose nor too dense. In stiff and poor soils they are 

 spare and scraggy, whereas in such as are at once deep 

 and loose, the minutest fibres both expand, and elongate 

 with facility, and render the mouths that search for food 

 to the plant almost innumerable.f This is remarkably 

 exemplified in the Beech and the Sycamore, and still 

 more in the Ash, of which the fibrous roots sometimes 

 amount to millions. Such soils, accordingly, furnish the 

 best rooting ground, and are always favourites with the 

 planter. To fit trees, however, for removal to situations 

 of great exposure^ the roots may, by artificial methods, 

 be multiplied to a degree far beyond what can be accom- 

 plished by unassisted nature ; and thus, by art discreetly 

 employed, the business of vegetation — that is, the circula- 



* Note IV. 



t Dii Hamel, Phys. des Arbres, torn. i. p. 82, Ellis, Veget, Anat. in Sup. to 

 Encyclop. Britan. 



