116 FORESTS, WOODS, AND TREES 
estimated the average annual yield to be 60 cubic feet per 
acre, or a gross return of 30 shillings per acre, spruce 
finding a ready sale here at 6d. per cubic foot as pit 
timber. 
In the Peak District a plantation of about 1000 acres, 
lying in the Goyt Valley, south-west of Taxal, extends up 
to 1700 feet elevation ; but all the trees that were planted 
in exposed situations at high altitudes or on wet moorland 
peat failed completely. Beech is vigorous and healthy up 
to 1250 feet, and conifers flourish to about 1500 feet 
elevation in this plantation. Spruce plantations on Kerry 
Hill in Wales succeed fairly well up to an elevation of 
1500 feet. 
On the west coast of Scotland, and in Ireland generally, 
the timber-line, owing to the strong prevailing wind, is con- 
siderably depressed as a rule. In the Wicklow Mountains 
there are, however, good conifer plantations up to 1200 feet 
elevation in situations sheltered from the west wind. 
It is often asserted that 1000 or 1200 feet represents 
the upper limit of profitable afforestation ; but there is no 
definite line, as so much depends on the presence or 
absence of shelter and on the nature of the soil. In most 
parts of Great Britain the elevation to which plantations 
may extend varies between 1000 and 1500 feet; but in 
the west of Scotland and in the greater part of Ireland 
there are many localities where trees cannot be successfully 
planted above 700 feet. Even in the south of England 
proximity to the west coast makes plantations at a high 
altitude unprofitable. On Exmoor, west of Porlock, 830 
acres of the Ashley Combe estate, between 1000 and 1400 
feet elevation, were planted in 1850-1860 with larch, 
spruce, and Scots pine. In 1913 the plantation was 
reported to have been a failure financially, 500 acres being 
a dead loss, while “200 acres . .. will never develop 
into marketable timber and are not worth more than what 
has been spent on them in cleaning, thinning, etc., without 
reckoning anything for the cost of planting and rent of land. 
Only 100 acres in the most favoured situations have given 
