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lion. This is freqiu-ntly observed ; 

 particular!}' in plants raised in wa- 

 ter only. The tap roots shoot out 

 branches which extend horizon- 

 tall)' ; and these brandies are 

 stronger, in (iroportion a« they are 

 nearer to the surface of that layer 

 of earth, which is stirred by the 

 plough or spade. 



These are the roots which we 

 callitig creeping or fibrous. They 

 extend sometimes to a considera- 

 ble distance from the plant that 

 produced them ; but then they be- 

 come so tninute, that the naked 

 eye can no longer trace them ; es- 

 pecially when they have taken the 

 tincture of the earth that surrounds 

 them, as they generally do. 



A carrot, for an example, which 

 seems to have only one great root, 

 furnished with some fibres, pushes 

 its roots, according to Mr. Tull, to 

 a considerable distance ; but they 

 grow so very slender, that they 

 cannot be distinguished from the 

 earth that covers them, without 

 great attention. The case is the 

 same with almost all plants. 



To convince the reader of this, 

 and at the same time to shew how 

 far the roots of plants can extend 

 in ground that is well loosened, he 

 recommends the experiment which 

 I have mentioned under the article. 

 Pasture of Plants, which see. 



The . following instances, sa)s 

 M. Duhamel, shew what effort 

 trees will make, to find a proper 

 soil for the extension of their 

 roots. On examining those of a 

 hedge, at the side of which a ditch 

 had been dug, it appeared, that 

 after passing underneath the ditch, 

 they reascendedj and spread them- 

 46 



selves in the ploughed earth on 

 tlie other side. 



He made the same observation 

 on a row of elms, which were very 

 near benig killed by the digging of 

 a deep ditch pretty near them, in 

 order to prevent their roots from 

 damaging an adjacent piece of 

 groinid. The elms shot out fresh 

 roots in the loose mould that drop- 

 ped into the ditch ; these roots re- 

 ascended on the other side of the 

 ditch, and spread in the ploughed 

 ground, and the elms soon recover- 

 ed their former vigour. 



He likewise observed, that on 

 digging a trench at a small distance 

 from a young elm, and filling it 

 with good mould, the roots of that 

 elm took their direction towards 

 the trench, and grew to a great 

 length in it. 



These observations prove that 

 horizontal roots extend far, espe- 

 cially in loose mould : And as a 

 plant thrives in proportion to the 

 length of its roofs, Mr. Tull justly 

 infers the necessity of keeping the 

 earth in tillage in a light state, 

 that the roots may easily penetrate 

 it. 



A root that has been cut or bro- 

 ken, never grows longer, but soon 

 produces several new roots, all of 

 which gather the proper food of 

 the plant. Its means of subsistence 

 are therefore increased, by the 

 breaking of its roots, in digging or 

 ploughing, rather than otherwise. 

 In the horse-hoeing husbandry 

 many of the fibrous roots of the 

 growing plant* are undoubtedly 

 cut off by the plough. But it oc- 

 casions the multiplying of the roots, 

 and consequently the greater nour- 

 ishment of the plants. 



