140 TRANSACTIONS OF ROYAL SCOTTISH ARBORICULTURAL SOCIETY. 
book which was prepared in anticipation of our visit, will show ~ 
in what proportions they are held :— 
Acres. 
State woodlands, ; ; ; : ‘ 62,600 
Communal woodlands, : ; : » (305,455 
Public establishments’ woodlands, : , 17,380 
Private woodlands, . ‘ : . i. S2hgee 
Total, : . Wy303;9se 
At the forest of the Hertogenwald, near Verviers, which was 
visited on 14th August, a very successful experiment in the 
planting of spoil-heaps was seen. After trying almost every 
likely species of tree, it was discovered that the white alder 
(Alnus incana) was the best for the purpose, inasmuch as it 
rooted freely, and wherever the roots came near the surface 
young suckers shot up round the parent plant, and formed a 
sort of copse, thus binding the heap together. At planting, 
each alder plant received a double handful of soil, carried to 
the spot in a basket. Very large heaps of loose stones lying 
on the hill-side had also been planted in this way with birch. 
The forest of the Hertogenwald is divided into three zones of 
altitude. In the lower zone, which has an altitude of from 770 
to 1300 feet, the soil rests on the Lower Devonian rock, and is 
permeable and fairly fertile. The crop is usually coppice-with- 
standards, but it is intended ultimately to convert the whole of 
this portion into highwood. In order, however, to bring the 
whole of the woods into line with the working-plan, it is proposed 
to take two more rotations of thirty years’ coppice-with-standards 
from one section of this zone. ‘This zone is very liable to injury 
from fires, and in order to make the heathy ground of which it 
is composed less liable to danger of this sort, the oak standards 
have been underplanted with beech; but where the heather 
was very rough, Scots pine has been thickly planted, and on the 
highest altitudes spruce has been used, as the latter species is 
not so liable to damage from heavy snowfall as Scots pine. 
These thickets of Scots pine and spruce come in very useful for 
mining timber, which is always in great demand in Belgium. In 
England the working of each ton of coal involves a cost of 
sixpence for timber, but in Belgium the cost is tenpence per ton. 
In the middle zone, the altitude of which is from 1300 to 1590 feet, 
the soil is more or less of a clayey nature, but, sylviculturally, the 
