174 TRANSACTIONS OF ROYAL SCOTTISH ARBORICULTURAL SOCIETY. 
These do not to any extent affect the growth beneath, as their 
tops are light and well elevated. 
Scots fir mixed with oak or beech are managed according to the 
class of the locality. Where the overlying soil is more suitable 
for fir than for the others, but where that underneath is of a 
better quality, this mixture is sometimes adopted. At the end of 
the rotation of 120 years, about 80 per cent. of the wood is 
composed of fir, and the balance of oak, with a soil-protection 
wood of beech. When beech takes the place of oak, the relative 
percentages are the same. Such a mixture, one hundred years 
of age, was noticed near Eberswalde, the cubic contents of which 
per acre, beech and fir combined, amounted to 6130 feet quarter- 
girth measure. 
Another mixture obtains on soils of a better class, consisting of 
oak, beech, and Scots fir. The Scots fir and beech“are gradually 
thinned out, so that at the end of the rotation the oak only 
occupies the ground. Where the soil is of a lower quality, the 
oaks and firs exist as the overwood, while the beeches act as a soil- 
protection wood. At the end of the rotation the firs are removed, 
and the caks remain for another period of 120 years. At the same 
time, it may be necessary, so that the ground may be fully stocked, 
to allow part of the beech to move up along with the oaks, and with 
them complete the final rotation of 240 years. These woods are 
regenerated in various ways, but the method of working is chiefly 
by the “group system.” Small sections of a convenient form are 
cleared, and these are restocked either by seeds or transplants, and 
when they are fairly stocked and established, other sections are 
taken in hand, and treated in a like way, until the whole wood is 
gone over. Again, where oak and beech occupy the ground at 
the end of a rotation, they are strongly thinned, so as to induce 
seed-bearing. When that is attained, and a seed year comes 
round, the soil is prepared by hoeing or harrowing for the recep- 
tion of the seed, and if a good stocking has resulted, nothing more 
is required, but if patchy, then seed may be artificially introduced, 
or plants removed from the stocked ground are inserted instead. 
Particular care has to be taken after regeneration that those 
plants of a vigorous habit do not choke out their neighbours, and 
that the parent trees are not removed until the young growth is 
out of danger from frosts. 
When a pure cak wood, which is usually under-planted with 
beech, fails to be naturally regenerated, the latter, with a few 
