24 



immediately, and in no case used for planting- out. 



The colour of the bark varies in different trees from 

 whitish-grey to dark brown. Trees with a whitish bark 

 are less desirable than the brown ones, as the former 

 are generally thinner. 



Not infrequently, trees are found with a knotty bark, 

 and the cause of this phenomenon need not be attributed 

 to parasites, it may be based on variation (see fig. 10). 

 Attention should also be drawn in passing to the 

 small round wooden knobs which are found in great 

 quantities on some trees and which have been formed 

 by the excrescence and pruning off of adventitious buds. 

 These are not caused by parasites nor can they be 

 attributed to tapping too deeply, as they are found, 

 although to a smaller extent, in trees that have never 

 been touched by the tapping knife. 



2. SEEDS AND NURSERIES. 



The method of sowing the seed depends on the manner 

 of planting that is to be adopted. This may be carried 

 out in three different ways : 



1. Seeds at stake. 



2. Stumps. 



3. Basket plants. 



In the first of these the seeds are sown directly in 

 the position which the trees are subsequently to occupy 

 and no nurseries are required. Seedlings are usually 

 however preferable. 



When baskets are used, these are placed close together, 

 so that they may support each other, and the neigh- 

 bourhood of an older plant is chosen for the purpose, so 



