340 TRANSACTIONS OF ROYAL SCOTTISH ARBORICULTURAL SOCIETY. 
Ross-shire which promises to provide a satisfactory solution of 
the difficulty. He now plants pure larch woods, and when the 
trees are sixteen to twenty years old he removes all the stems 
except the soundest and most promising, of which 300 to 500 
are left per acre. Needless to say, the system is inapplicable to 
cases where all, or practically all, the trees are attacked by 
disease at this early stage, but instances of such virulence are, 
on the whole, of rare occurrence. The trees that are retained 
are the picked stems of the three to four thousand originally 
occupying the ground, and measure up to 51 feet in height and 
4 to 8 inches in diameter at breast-height. Stems that are sound, 
or fairly sound, at this stage are not likely to suffer much from 
disease in later life. The thinnings removed realise £20 to £ 25 
per acre, giving a return therefor of fully #1 per acre per 
annum from the time of planting. The thinning is done as 
early in autumn or winter as possible, and the next step is to 
knock off all the lower dead branches of the trees that are 
retained. ‘This is a rapid process, and is accomplished by means 
of a pole some 8 feet long. The “top and lop” of the felled 
larches, along with the dead branches cleared off the standing 
stems, are then thrown together into small heaps and burned. 
Owing to the shading of the dense crop of larch the surface 
of the ground is clear of all grass and similar vegetation, and is 
in a very suitable condition for the reception of fresh plants. 
Without loss of time the area is stocked with an underwood 
which, of course, must consist of species that can endure the 
shade of the 300 to 500 larches that have been retained. Mr 
Munro Ferguson at first used the Norway spruce, silver fir, and 
beech, but was not satisfied with the results obtained with any 
of these. The Norway spruce was found to grow very slowly 
under the circumstances indicated, while the silver fir in this 
particular locality is so much attacked by aphis (Chermes adietis) 
as to be very uncertain in its growth. Better results were 
obtained with the beech, and although this tree is now super- 
seded by other species, it will probably be found to be the most 
suitable for use on the chalk, and on calcareous soils generally. 
But for some years Mr Munro Ferguson has been experi- 
menting with other shade-bearing trees, and has found that 
Picea sitchensts (Abies Menztesit), Douglas fir, Zsuga Merten- 
stana, Thuya gigantea, Cupressus Lawsoniana, and Abies grandis 
are far superior to the three species previously mentioned. 
