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laid down is to thin very lightly till the full height- growth 

 has been reached, taking out only those stems that are 

 manifestly suppressed by their stronger neighbours. If 

 this be not done, it is generally of little consequence, 

 beyond the loss of the market value of the dominated 

 stems. But when the full height-growth has been reached, 

 thinning becomes imperative, and the plantation should 

 then be gradually opened out till large well-developed 

 crowns are secured. In this process all the weak crowns 

 and crowded stems are gradually removed. The golden 

 rule in thinning is never to cause a permanent gap in the 

 leaf canopy. As long as the leaf canopy is preserved 

 unbroken, there will be little loss in the production of 

 wood. Experiment has shown that a Blue-gum plantation, 

 as long as the ground was completely covered by the 

 crowns, produced the same increment of wood with 50 as 

 with 500 stems per acre ? 



Leaf-shedding Trees. 



Deciduous or leaf-shedding trees are usually easier to 

 rear and easier to plant out than evergreens. Some, such 

 as the Poplars, Willows, Plane, Catalpa and Ailantus, only 

 require slips to be placed in the ground in Spring to 

 produce trees in a few years. Trees the size of a man can 

 be shifted with little risk during Winter, when the leaves 

 are off. But leaf-shedders are usually natives of countries 

 with cold winters, where the frosts disintegrate and enrich 

 the soil, and they do not succeed in the poor soils where 

 Wattles and most oi the Pines and Gums flourish. In 

 S. Africa they usually grow best where the winters are 

 most pronounced, i.e., the S.W. districts and inland at some 

 eleration. 



The changing of their foliage, their Autumn tints, and 

 fresh beauty in Spring after the short Winter, combine to 

 render them favourites in a country where the native 

 vegetation is evergreen, and dull with the monotony of 

 changeless beauty. 



I shall only mention those leaf-shedders that are hardy 

 over considerable areas in S. Africa. 



C 2 



