Clay is assuredly _not_ the proper soil for spruce and silver fir; their exceedingly numerous, soft, fibrous, moss-like rootlets, require an easy damp soil. {340} We have tried a number of kinds of abies, in both dry and moist clay, and have found they did not grow so luxuriantly (thrive so well) as Scots fir or larch. The silver fir shewed superior adaptation to any of the other kinds of abies. Almost in every instance where we have seen the silver fir and Norway spruce (by far the best spruce for Scotland) growing together, the former was the superior. The timber, in the lower part of the stem, is harder than that of the spruce, but freer and more porous in the upper part. It is probable that the silver fir will not thrive in so elevated or so moist a situation as the spruce, but in all favourable soils it merits a preference. We now come to a very important part of our author’s volume—an account of the most economical, and, as he says, the most successful, mode of planting moors and bleak exposed mountains, but which is brought forward by him under no limitation to place. To the invention of this method, our author lays no claim; he merely describes the practice in a clear and judicious manner. “The most proper time for removing firs from the nursery to waste land, is when they are two years old.”—“The experience I have had enables me to say, with as much confidence as I can speak on {341} any point whatever, that the longer any fir is allowed to remain in the nursery after it has attained two years’ growth, so much the less chance is there of its success when removed to its final destination.”—“At this period (two years’ growth) larches may be obtained transplanted, as it is customary to put considerable numbers of them out into nursery-lines when they are one year old. Such plants have better roots than those that have remained in the seed-bed till they are of the same age; but as their price is considerably higher than that of the latter, it is somewhat doubtful whether they are so much superior in quality as to compensate for the greater expense. At all events, healthy larches from the seed-bed have never failed to give satisfaction when properly planted in soil suitable for them. Other species of fir are scarce ever transplanted in the nursery till they are two years old, so of this age there is no choice left but to take them from the seed-bed.”—“Birch, alder, and mountain ash, succeed well when removed from the nursery in their second year.”—“Beech and plane do not succeed well unless they have stood some time (two years at least) in nursery lines, after having been removed from the seed-bed.” “The pitting system of planting should be {342} adopted in every instance in which the plants exceed two years old.