TREES FOR WATER CATCHMENT AREAS 129 
In the west of Scotland, Wales, south-west England, and 
Treland it is at home from sea-level up to 1000 or 1200 
feet elevation; and is adapted for the zone of hill pasture 
wherever the soil is moderately deep. It is not suited 
for the heather moor or heaths, where pine and larch are 
the successful species. Silver fir is a good wind-resister, 
and attains a greater height in the teeth of the wind, 
whether inland or close to the sea, than any other species. 
This great height-growth enables it to produce a large 
volume of timber in moderately exposed situations. Used 
as a shelter belt in wind-swept districts, it will protect 
other species planted in masses to leeward and greatly 
augment their production of timber. Shelter belts of silver 
fir mixed with beech would also greatly improve pasture 
lands in the west of Ireland, Wales, etc. 
In the young state silver fir is liable to spring frost, 
and on that account may occasionally require the protection 
of nurses in its early stage; and for this purpose hornbeam 
or birch may be used, planted either with the silver fir or 
one or two years previously. Silver fir may be planted 
pure or mixed with beech or spruce; and for many years 
should be kept dense on the ground in order to produce 
well-shaped clean stems. 
In Ireland silver fir scattered in mixed woods regener- 
ates itself very freely, as the seedlings spring up in great 
numbers amid the ordinary woodland herbs, and grow well 
in the partial shade. Shelter belts and plantations of 
silver fir mixed with beech, sycamore, and ash could always be 
naturally regenerated, and would often be very remunerative. 
The timber ordinarily produced by silver fir in this 
country has been rough, branched, and knotty, as it was 
usually thinned too early or mixed with unsuitable species 
like Scots pine. Grown in complete canopy, it produces 
an extraordinary volume of timber, only surpassed in this 
respect by Douglas fir and Sitka spruce. On favourable 
sites 100 to 120 cubic feet per acre per annum may be 
expected. Grown close the timber is narrow-ringed and 
of excellent quality. 
K 
