74 TRANSACTIONS OF ROYAL SCOTTISH ARBORICULTURAL SOCIETY, 
as it is sometimes called, must on no account be long delayed, other- 
wise the effect on the young generation will prove very prejudicial. 
In the latter case, the subsequent felling should be made in the first, 
or at most in the second, autumn after the seed has germinated, 
when the whole of the trees may be removed in either one or two 
fellings ; or twenty to thirty per acre may be retained as standards 
to grow through the whole of the second rotation, and so form extra 
heavy timber. In the case of the beech, spruce, silver fir, etc., the 
subsequent felling should be subdivided into several fellings, the 
last of which—~.e., the final felling—need not be undertaken till ten 
or more years after the seed felling, though during that time a con- 
siderable number of trees should be removed every year or so in 
order to satisfy the increasing demands for light on the part of the 
young trees. 
Speaking generally, the subsequent felling should be most quickly 
performed on poor dry land, because the shade trees partially prevent 
the entrance of rain, and yet are so scarce as not to be able to hinder 
evaporation to any appreciable extent. On north or east slopes, 
also, or at high elevations, where the growing season is short, the 
retention of many old trees for a considerable period would retard 
growth in the young trees to an undesirable extent, 
On the other hand, the subsequent fellings should not be hurried 
where late frosts are almost annual in their recurrence, as well as on 
all strong soils, especially those resulting from the weathering of 
limestone, basalt, or porphyritic rocks, because there strong weeds 
are to be apprehended ; and besides, on such rich soils trees can bear 
an amount of shading with impunity which would soon kill them 
on poorer soils. 
It is needless to say that very great care and skill are required in 
felling the old trees after the young trees occupy the ground, so as to 
prevent the latter being excessively damaged. Unless snow cover 
the ground, all operations should be suspended during hard frost, as 
at that time the young stems are very brittle, and specially liable to 
be broken. Where the trees are provided with large branches, they 
must be pruned before being felled, an operation entailing a great 
deal of labour, but one which it is impossible to avoid. 
The system which has been sketched, namely, the simultaneous 
natural regeneration of whole woods under shade trees, has the 
advantage that the operation in all its phases is confined to a limited 
period, and is concentrated into a compact area, so that the work 
can be easily controlled and directed. If all goes well, then a large 
