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ROOTS, 



ROOTS, 



The root is the organ througli which food is conveyed from the earth into the 

 plant, and is the part which is soonest developed, increasing in length by the 

 addition of new matter at its point, much as an icicle by the constant superposi- 

 tion of layer over layer, with this difference, that the icicle is augmented by the 

 addition of matter from without, while the root lengthens by the perpetual crea- 

 tion of new matter from within. Being furnished with the power of perpetually 

 adding new living matter to their points, they are thus enabled to pierce the solid 

 earth in which they grow, shifting their mouths in 

 search of fresh pasturage; hence the expression, 

 " You may feed your trees as well as your chick- 

 ens." A Populus monilifera, Canadian poplar, has 

 been known to send a root thirty feet horizontally, 

 including its dip beneath a wall, and then to have 

 passed into an old deep well to the depth of eighteen 

 feet. A deciduous cypress-root, eleven feet long, 

 passed nearly to that length without division, in 

 search of water. Willows exhibit even greater de- 

 sire to travel in search of nourishment. 



It is not merely in length that the root increases, 

 or else all roots would be mere threads ; they also 

 augment in diameter, simultaneously with the stem. 

 Neither is it by an embryo alone that roots are 

 formed. A plant once in a state of growth, has 

 the power of producing roots from various parts, 

 especially from leaves and stems. A Spanish chest- 

 nut, between ninety and one hundred years old, was 

 cut down in 1849. With the exception of its foliage, 

 which always had a yellowish sickly tinge, there was 

 scarcely anything else that indicated decay. Its 

 trunk seemed perfectly sound, with healthy annual 

 shoots, No sooner had the workmen commenced 

 cutting, than it was discovered that for ten feet 

 high, as much as two-thirds of the bark round the 

 trunk was dead and reduced to a mere shell. On 

 removing this thin covering, the sap-wood was found 

 to have become a mass of decayed vegetable matter, 

 through which a complete network of roots passed to 

 the ground, as represented in the cut, and extended Fig. 1. 



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