l6o TRANSACTIONS OF ROYAL SCOTTISH ARBORICULTURAL SOCIETY, 



effaced. This, then, would seem to have very little claim to the 

 title "woodland," but may be rather classed as something between 

 that and pasture. In fact, because of the xerophilous nature of 

 the grassland, the rich growth of grass between the trees, the 

 sparse stocking of the wood, and the absence of undergrowth, 

 "scrub" may be more applicable to it than any other term. 

 Finally, although much of this birch scrub would seem to be the 

 result of grazing, it is possible that on the upper limits of tree- 

 growth, where the influence of grazing is reduced to a minimum, 

 and where only natural factors exist, the birch may be very little 

 altered from its most primitive state. 



Scots Pine "Urwald." 



This type occurs as pure forest, typically on the middle valley 

 slopes, and has a much more restricted range than birch, which 

 occupies positions at higher as well as at lower elevations than 

 Scots pine. Like birch, it often assumes a strip formation, tapering 

 off at one or both ends, or, in the form of a wedge, it may extend up 

 " dry " and river valleys, with the apex reaching the highest eleva- 

 tion, as is seen in the Cairngorm district. Again, it may occur as 

 small groups of only a few trees studded along a valley slope, and 

 completely surrounded by birch. One may take this type as 

 being more or less restricted to the Highlands, although, in 

 Galloway, an example is said still to exist, and all accounts seem 

 to indicate that it represents the remains of the great central forest 

 of Scotland. Sir Thomas Dick Lauder, in his Moray Floods, 

 refers to " these immense tracts of pine still covering the 

 country at the roots of the Cairngorm mountains," as "the relics 

 of the great central forest of Scotland." In the same work, he 

 thus describes a cut through the Moss of Cluihaig, where, in 

 lo to 15 feet of peat, six or eight strata of roots of trees were 

 obtained: "The lowest stratum is of birch roots, about 2 feet 

 above the gravel the moss rests on. Then come three successive 

 strata of fir {i.e. Scots pine) roots, 18 inches apart — another 

 stratum of birch roots — and above that one or two more of fir 

 that do not seem to have attained any great size. Lastly, there 

 are firs now rooted and growing on the surface, but these are 

 small and stunted and are called, in the language of the country, 

 darrachs." This affords an excellent example of the natural 

 rotation of virgin forest, and also bears out the above statements 

 regarding the relative ranges of Scots pine and birch " Urwald.'' 



