290 TRANSACTIONS OF ROYAL SCOTTISH ARBORICULTURAL SOCIETY. 
ground, that the making up of failures is entirely neglected. Now 
this is a great mistake when the rearing of a full crop of clean- 
grown timber is aimed at, The more space trees are allowed for 
the growth of side branches, the coarser and knottier will be the 
timber. It is of the utmost importance, therefore, that every 
blank should be filled, and the ground completely stocked. Grass, 
whins, briers, and other rubbish should be kept down when they 
are likely to overtop or damage the plants in any way. When 
once properly established in the ground, and growing freely, the 
trees are able to take care of themselves, and ultimately smother 
out undergrowth of every sort. 
Pruning.—This will commence the first year after planting. 
All the plants should be carefully examined, and wherever one is 
found to have become sickly, from any cause, it should be cut over 
at the surface of the ground. This will cause it to send up a few 
shoots from the root. These shoots are all cut away the follow- 
ing summer, except the strongest one, which is retained as the 
future tree. Moderate annual prunings are better than severe 
prunings at long intervals. What is aimed at is to restrict the 
plant to one leading shoot, and to prevent the laterals from 
developing too much at the expense of the stem. If a proper 
stocking of trees is maintained on the ground, this is all the 
pruning that is required. It is an expensive operation, and 
requires a greater amount of skilled labour than is generally 
obtainable. Although it cannot altogether be dispensed with in 
the case of hardwoods, the less pruning trees require the better. 
No doubt trees are benefited by having limbs and large branches 
removed, as much of the nutriment that would go to feed these is 
utilised by the stem, and evaporation by the leaves is restricted, 
but the blemishes caused in the timber by the operation of pruning 
more than counterbalance any such benefit. By maintaining a 
proper distribution of the trees on the ground, the necessity for 
pruning will be greatly lessened. 
Thinning.—We frequently hear the advice given, ‘‘thin when 
the branches begin to touch.” ‘This is wrong. Take, as an 
example, the Scots pine. By thinning to the extent indicated, 
the branches are allowed to spread and enlarge to a considerable 
size. These branches will, in the course of time, die and drop off, 
but before this takes place, large black knots will be enclosed in 
the stem, and the quality of the timber will suffer in consequence. 
Light is also too freely admitted to the lower part of the stems in 
