1810. 



THE CKNESHE l-WKMEIt. 



99 



BOTANY. -THE ROOT. 



Tiik Root consitutes tin- basis of the plant: h 

 serves two purposes in the vegetable BOonomy-*-first 



to fix the plant mechanically in the soH ami retain ii 

 in its position— secondly to absorb from the soil those 

 inorganic elements which are aece sary for its 

 The general direction of the root is downwards; but 

 the roots of various plants grow at all I I 

 thf horizontal to the perpendicular: the principal 

 perpedicnlar axis is called the tap root. The number 

 ami extent of the roots must correspond with those 

 of the stalk and leaves of the plants, in order to sup- 

 ply their demand of food from the soil. 



Roots do not usually extend to great depths, but 

 keep within the limit of that portion of soil which 

 supplies their proper nutriment. Roots are distin- 

 guished from stems and branches by the absence of 

 6tomata, buds and pith — and by the presence of ab- 

 sorbing fibres. 



The stock, or main body of the root, sends off the 

 fibrils, or minute, slender branches of the root, — the 

 delicate, tender extremities of the fibrils are called 

 spongioles; these are the growing points, and the 

 organs which absorb from the soil the earthy part, of 

 the food of all plants. If some trees, as the willow 

 or currant, be inverted in the soil, the branches are 

 changed to roots, while the roots put forth leaves in 

 the air, and the plant grows. 



Roots are of several different forms, which have 

 received specific names for the sake of convenience. 



Fig. 



Fig. 3. 



Ramose, or branching roots are those which send 

 off many ramifications in various directions, like the 

 branches of a tree: such are the roots of the oak, &c. 

 Fusiform, or spindle shaped roots, con- 

 sist of a fleshy stock, tapering downwards 

 to its extremity, sending off fibrils, which 

 are its true roots: such are the radish, car- 

 rot and parsnep. Fig. 2. 



The napiform root is 

 a variety of the fusiform, 

 in which the neck or 

 upper part swells out, so' 

 that its diameter equals 

 or exceeds its length. 

 The turnip and turnip- 

 radish are examples. Fig. 3. 



Fibrous roots are 

 made up of numer- 

 ous small thread-like 

 roots, attached di- 

 rectly to the stalk, 

 without any neck or 

 main root : such are 

 the roots of most 

 grasses. Fig. 4. 



Fasciculated roots differ from the fibrous in having 

 of their fibres thicken i and fleshy, as in the 



dahlia and pii-ouv. 



Tuberov* roots consist of fleshy, 

 lisfa knobs or tumors, at. or 



the i stremity of the stalk, 



as in the orchis: '"the potato was 

 once classed among tubers, — but 

 as it uniformly hears buds, it is 

 '• among stems." Fig. 5. 

 Granulated roots consist of 

 many small rounded bulbs con- 

 nected by fibres, as in the com- 

 mon wood sorrel. Fig. 6. 



Fig. 6. 



Besides these varieties of roots, there are several 

 otheis which are peculiar; and distinguished by not 

 being necessarily fixed in the soil. 



Aerial roots are those which grow from some part of 

 the plant above the surface of the soil in the open air. 

 Some creeping plants, as the ground ivy, send forth 

 these roots from their joints. The screw-pine also 

 send off roots which are several feet in length before 

 they reach the ground. Such roots are often seen in 

 the common maize. 



Floating roots belong to plants which float upon 

 the surface of water. The water-starwort is said to 

 float upon the surface until flowering, when it sinks 

 and takes root in the mud till its seeds ripen. 



The epiphytes, or plants fixed upon the branches 

 of other species, derive their nourishment mostly 

 from the air; such are some species of moss. 



Parasites are those plants which grow upon other 

 plants; and some of whose roots are said to penetrate 

 their tissues and subsist upon their juices; while the 

 roots of others are aerial, and derive their food from 

 the air: such are the mistletoe and dodder. 



Roots are divided again into three varieties, viz: 

 annual, biennial and perennial, according to their 

 duration. 



Annual roots are those which live only one year, 

 and must be raised from the seed^ sown every spring, 

 — as beans, peas and cucumbers. 



Biennial roots are those which live two years and 

 do not blossom the first season, — but they produce 

 flowers, fruit and seeds the second year, and then die; 

 such are the beet, cabbage and carrot. 



Perennial roots live several years, — some of them, 

 as forest trees, live to a very great age: the grasses, 

 dandelion and asparagus are other examples. — Kodg- 

 ers* Scientific Agriculture. 



Pomological Rkform. — A. J. Downing, Esq., 

 chairman of the General Fruit Committee of the 

 Congress of Fruit Growers, has addressed a circular 

 to the committee, directing their attention to the 

 necessary subjects for investigation. It is an impor- 

 tant document, and we shall call attention more par- 

 ticularly to it at a future time. 



