PROTECTION OF YOUNG SPRUCE FROM FROST. 289 
height not exceeding 3 feet, while the colour of the foliage is 
a dull yellowish-green instead of the natural dark green of the 
sheltered plants. In short, those trees which were planted 
underneath the uniform shade of the birch standards are at 
present 50 per cent. better than are those which were planted 
in the open. 
What has been clearly demonstrated in this case is, in my 
opinion, so important that it is well worth bringing before the 
notice of all those who are in any way interested in the growing 
of spruce. Generally speaking, it may be laid down that in 
most places where the birch readily reproduces itself the soil 
will be found of such a nature as to justify the growing of 
spruce. In many outlying districts, ten or twelve years old 
birch is of no practical value, and in such instances it is 
customary for the forester to look upon it as nothing more than 
a weed which has to be cut down and burned before another 
crop can take its place. To all those who have to deal with 
areas of this description I would strongly recommend that as 
many of the natural birch standards be left on the ground as 
may for a time afford protection to the coniferous crop, more 
especially if this consists of Norway spruce. 
A natural question to ask here is, how long should the birch 
standards be allowed to remain over the young crop? In the 
plantation under review, the whole of the birch were removed 
during the autumn of last year, or five years after the spruce 
trees were planted. This was done because, in the first place, 
it was considered that the young plants had overgrown the frost- 
zone, which I consider is most destructive at from 2 to 3 feet 
above the surface of the ground;! for once the spruce reaches 
a height of 4 feet and upwards, the injurious effects of frost are 
reduced to a minimum. Secondly, they were removed because 
of their tendency to overdraw the young trees; and in the third 
place, it was considered desirable to remove them while they 
were light enough to allow of their being carried out of the 
plantation on men’s shoulders, as otherwise a considerable 
amount of harm would have been done to the spruce if the use 
of horses had been necessary for the dragging out of the birch. 
Yet another, and not less important, reason for their removal at 
1 The actual depth of the frost-zone at any point will, of course, depend on 
the configuration of the ground.—Hon, Ep. 
