Chap. II. F L E A V fi S. ^ 



The following inftances, fays M. Duhamel, fhew what effort trees 

 will make, to find a proper foil for the extenfion of their roots. 



On examining thofe of a hedge, at the fide of which a ditch had 

 been dug, it appeared, that after pafling underneath the ditch, they 

 re-afcended, and fpread themfelves in the plowed earth on the other 

 fide. 



He made the fame obfervation on a row of elms, which were 

 very near being killed by the digging of a deep ditch pretty near 

 them, in order to preveht their roots from damaging an adjacent 

 piece of ground. The elms fhot out frelli roots in the loofe mould 

 that dropt into the ditch : thefe roots re-afcended on the other fide 

 of the ditch, and fpread in the plowed ground, and the elms foon 

 recovered their former vigour. 



He likewife obferved, that on digging a trench at a fmall di- 

 flance from a young elm, and filling it with good mould, the roots 

 of that elm took their direftion towards the trench, and grew to a 

 great length in it. 



He alfo gives an infi:ance of two elms blown down by the wind, 

 which had fi:ood upwards of an hundred years, whofe original 

 roots, being planted too deep, had not increafed in all that time, 

 but the trees had been fed by other roots which (hot out nearer the 

 furface of the earth. 



Thefe obfervations prove that roots extend themfelves to a great 

 diftance in the earth, efpecially when the mould is loofe : and as a 

 plant thrives in proportion to the extent of its roots, Mr. Tull 

 juflly infers the neceflity of keeping the earth in a light flate. 



A root that has been cut or broken, never grows longer, but 

 foon produces feveral new roots, all of which gather the proper 

 food of the plant. Its means of fubfiftence are therefore increafed 

 by the breaking of its roots in digging or plov/ing. 



C H A P. IL 



Of LEAVES. 



LEAVES are fo necefi"ary to plants, that few can fubfifi; with- 

 out them : for experience fiiews, that if they are llrip'd of all 

 tlieir leaves, they generally die. I fay generally, becaufe we fome- 

 times fee trees ftrip'd by infedts, which do not die. M. Duhamel 

 mentions his having killed trees by taking off all their leaves. Is this 

 difference, fays he, owing to the infefts defiiroying them by degrees, 



B 2 or 



