EAELY CULTIVATION OF PLANTS. 



355 



which are often not more than two inches in diame- 

 ter — the roots become matted and twisted round the 

 interior of the pot ; and this process may be repeated 

 at each successive shifting, till the roots have assumed 

 the form of a bird's nest, and the upper part of the 

 plants have been in a great measure stunted. They 

 are frequently transferred to the open ground without 

 any efficient attempts being made to spread out the 

 roots on the surface; and when the separation of the 

 roots is resorted to, it may be so violent as to give a 

 considerable check to the growth, for which reason it 

 is often employed with reluctance ; indeed, in old pot- 

 grown plants, whose roots have acquired a firm set, 

 the operation may be impossible ; in which case it will 

 be more satisfactory to throw them away than to plant 

 them, for they are almost sure to be upset by the wind 

 when they have attained the height of fifteen or twenty 

 feet. Most of the pine tribe have few or no tap roots. 

 They spread their principal roots all round near the 

 surface of the soil ; and these roots, being more or less 

 at right angles to the trunk, according to the slope of 

 the ground, afford the tree a primary rest or support, 

 independently of the hold which, as roots, they take 

 of the soil. Of course this advantage is greatly less- 

 ened, if not wholly lost, by pot-culture. Nevertheless, 

 this mode of propagation can not be wholly discon- 

 tinued. Some pines are undeniably tender while 

 young. The facility with which plants can be turned 

 out of pots with good balls, is of considerable value. 

 For these reasons, this method of cultivation should 

 be, if possible, improved, and its disadvantages sedu* 

 lously remedied. "We would recommend the employ 

 ment of wider and shallower pots than those in 



