42 JOURNAL OF THE ROYAL HORTICULTURAL SOCIETY. 



The main conditions to be observed in forming such mixtures 

 are : First, that the most valuable species shall dominate or grow 

 most rapidly, and the other, or others, be subservient to it, so 

 that the latter shall at no period of growth interfere injuriously 

 with the former ; or, second, that the different species shall be of 

 the same rate of growth and possess similar habits and require- 

 ments as regards light, heat, moisture, &c. In the former case 

 certain species are introduced for the benefit of the main crop ; in 

 the latter all are on an equal footing, or practically so. Examples 

 of such mixtures are found in growing Beech with Scotch Pine, 

 Larch, or other fast-growing Conifers, in which the latter form 

 the dominant species, and the Beech is kept at a lower level by 

 reason of its slower growth. Oak with Spanish Chestnut, or 

 Beech with Hornbeam, furnish examples of mixtures in which 

 both species are pretty evenly matched. Another form of mixed 

 plantation is that wherein the main crop remains unmixed at 

 first, but a shade-bearing species is introduced after a few years' 

 time, so that the wood becomes what is technically known as a 

 " two-storied-high forest." A mixture of this kind is especially 

 suited for light-demanding trees, which require a long period to 

 mature, such as Oak, and is also advantageously adopted with 

 Scotch Pine and Larch, Beech being the favourite tree for the 

 second or lower story. 



We now come to 



Planting. 



So long as a plant is able to re-establish itself in its new habitat 

 without having its growth seriously checked, or its stability in 

 after-life impaired, one system of planting is as good as another, 

 if the aim of the planter is simply to leave a certain number of 

 trees which shall at some future period occupy more or less 

 completely the whole area planted. Such an object the arbori- 

 culturist might have in view, and, as arboriculture has been 

 long practised in this country, it is not surprising to find our 

 woods planted on more or less arboricultural principles. But 

 timber-growing and tree-growing are two different things, and the 

 methods which would be suitably employed in the case of the 

 one need not necessarily be so in the case of the other. Now good 

 timber is produced not only by laws of growth peculiar to each 

 genus and species, but by natural laws which are common to 



