PLAN FOR THE PIT-WOOD WORKING CIRCLE, RAITH ESTATE. 241 
should be made to ascertain the method of planting that is 
best suited to the locality, having regard to the expense involved 
in its adoption. 
THINNING. 
As the stock in the older woods is already too light, no 
thinning of green trees will be needed in them. But, from time 
to time, dead and dying trees should be removed, so as to realise 
their value, and to reduce the risk from fire and from dangerous 
insects, whose breeding-places they form; in Cardenden (6) and 
Dundonald Muir work of this kind must soon be undertaken. 
The general rule for thinning the younger woods and new 
plantations will be as follows :—The first thinning will be made 
as soon as the development of the crop has produced a number of 
dead, dying, and suppressed poles. These will then be removed, 
together with any others that may have become injured or mis- 
shapen. It is not yet possible to say precisely at what age the 
first thinning will become necessary; the oldest of the younger 
woods, planted 16 years ago, do not yet show signs of requiring 
it. They appear to have been planted at 3 feet intervals, and not 
to have been thinned, except in the case of Cardenden Colliery, 
where diseased larch, with some birch, were removed six years 
ago; and in Powguild, where some spruce and larch were taken 
out in 1894 and 1895; but it is probable that a good many 
deaths occurred, and that the vacancies thus caused were not 
effectively filled up. Thinnings of the above degree, which will 
reduce risk from fire and insects, should be repeated as often 
as may be found necessary—possibly every 3 to 5 years—until 
about 10 or 15 years before the wood is to be felled, ae., until 
about the 25th or 30th year in the case of crops that are to 
stand throughout the full rotation of 40 years, but up to an 
earlier year in the case of crops which, in the first rotation, 
are to be felled before that age. If, towards the conclusion of 
these thinnings, parts of the wood should be found where the 
growth has been so equal that but few of the individual trees 
have outstripped their neighbours, and where the even crop is 
consequently too dense and the growth in diameter too much 
retarded, a portion of the trees will be thinned out, in order to 
afford more growing space for those left. When the above group 
of thinnings has been carried out, it will probably be desirable to 
make a somewhat heavier thinning (A), in order to enable the trees 
