64 AMERICAN POMOLOGY. 



Here, as in other cases, our teachers have led us into er- 

 ror by attempting to trace analogy with animal anatomy 

 and physiology, and by directing our attention to the cir- 

 culation of plants, as though they, like the higher animals, 

 possessed true arterial and venous currents of circulating 

 fluids. The cell circulation is quite a different affair, and 

 can be conducted in either direction, as every gardener 

 knows who has ever layered a plant, or set a cutting upside 

 down. So with the roots they are 'but downward ex- 

 tensions of the stem ; under ordinary circumstances they 

 have no need for buds, but these may be, and often are 

 developed, when the necessity for their presence arises. 

 Buds do exist on roots, especially upon those that are 

 horizontal and near the surface, and from them freely 

 spring suckers, which are as much parts of the parent tree 

 as its branches, and may be planted with entire certainty 

 of obtaining the same fruit, just as the twigs when used 

 as cuttings, or scions, when grafted, will produce similar 

 results. 



Whole orchards are planted, in some sections of the 

 country, with the suckers from old trees ; apples, pears, 

 plums, and even peaches, as well as raspberries and black- 

 berries, are multiplied in this primitive way. There are 

 some varieties of apples that have been so propagated for 

 half a century, and extended for hundreds of miles in this 

 way by the pioneer emigrants, without .ever having been 

 grafted, until their merits have at length accidentally be- 

 come known to the Pomological Societies and nurserymen, 

 when the propagation of them by grafting soon super- 

 cedes the more primitive method. Sucker trees are ob- 

 jected to upon the grounds that they are not healthy and 



