20 TRANSACTIONS OF KOVAI. SCOTllSH AKIiOKICll/l TKAI. SOCIKTY. 



;^io8, 5s. per acre. The trees seem to be suffering from in- 

 sufficient moisture, and some of them are dying. As they are 

 now putting on very little growth, they should be cut down as 

 early as is convenient. Probably they would be in a better 

 condition if they had been subjected to a heavy thinning when 

 younger, but that is a difficult matter to express an opinion on, 

 and, in any case, they compare favourably with plantations 

 growing on similar situations on the Continent. Natural 

 regeneration is carried out on scientific principles, usually on 

 the strip or compartment systems. The nature of the surface 

 seems to allow of the seeds becoming easily covered, and a 

 very thick growth of young trees soon springs up. 



There is no sharp or well-defined boundary between this low- 

 lying and comparatively level area and the hummocky dunes 

 into which it gradually emerges. In parts the latter also are 

 well wooded, but those nearest to the large sand-hills are as yet 

 covered only with a few rabbit-pruned trees, which are struggling 

 to make headway in spite of the adverse conditions with which 

 they have to contend. 



The large sand-hills, of which there are several at Maviston> 

 flank these dunes to the north and west. Two of them are 

 of special interest on account of the manner in which they have 

 destroyed, and are continuing to destroy, the plantations lying 

 in their path (Plate II. Fig. 3). They have no bent growing ou 

 their surfaces, and are both making comparatively rapid progress. 

 One is proceeding westwards, the other and more important 

 eastwards. The latter is some 40 feet in height. It slopes 

 gradually to the west, but has on the east a bold bluff side 

 which makes an angle of about 40 degrees with the vertical. 

 It advances on the trees with all the regularity of a well- 

 formed embankment. After it has moved forward some 

 distance in its course, its victims, or rather their bleached 

 and whitened skeletons, again appear (Plate III. Fig. 4), Still 

 farther to the rear, where the sand has almost completely left 

 the devastated area, nature has begun to repair the damage. 

 At first the ground becomes covered with Xerophytic grasses,. 

 and also with /uncus sqtiarrosus^ species of Carex, trefoil, birch 

 and dwarf willow. A thin layer of peat is also present. Later 

 on, a thick growth of young Scots pine trees takes complete 

 possession, and will, in course of time, replace the wood which 

 has been destroyed. On the Brodie estate, the whole area under 



