172 THE DEVELOPMENT OF BRITISH FORESTRY 



carpa, as with some other species of that genus, merely 

 ceases its growth in autumn and resumes it in spring, 

 and it is doubtful if any precautions are effective unless 

 the trees are placed in sheltered situations. The difficulty 

 with this species appears to be its rapid growth and bad 

 root system, the latter consisting of a tap-root, and a 

 scanty supply of fibres which are easily broken and 

 damaged. 



Crowding in the nursery is a frequent cause of badly 

 ripened wood Avith many species. This crowding may 

 take place in the seed bed or in the nursery lines, and 

 in either case is conducive to long, drawn up, and weakly 

 plants. Of the two, thick sowing is preferable to thick lining 

 out, as the latter will weaken plants at a time when this 

 is most objectionable, and when they need all the vigour 

 and reserve strength possible at the time they are 

 planted out. Thin seeding and lining out, of course, 

 mean extra expense, and the nurseryman who tries to 

 sell, or the forester who wishes to buy, trees at the 

 minimum price per 1000 is neither likely to produce or 

 plant trees which possess the good qualities necessary 

 for successful work. Weakly plants are not only more 

 liable to suffer from wind or frost during the winter, 

 but they contain scanty stores of reserve material within 

 their tissues to renew damaged or destroyed parts. 

 When the growing points of the roots of such plants 

 are injured or lost through transplanting, the formation 

 of new roots proceeds on a very limited scale, and may, 

 under unfavourable conditions, fail altogether. In the 

 same Avay, the leaves and shoots pushed out by 

 weakly plants are feeble organs of assimilation, and do 

 little to carry on the growth of the plant for several 

 weeks. In fact, nursery crowding is bad for all plants, 

 whatever the species may be, and must be avoided if 

 good trees are to be obtained. 



