i02 transactions of royal scottish arboricultural society. 



Forest Growth. 



Oak. — The sessile oak is the predominant species, forming 



about half the crop, the general composition of which is as 



follows : — 



Percentage. 

 Oak, ..... 50 



Beech,. • • • • 35 



Conifers, . . .10 



Hornbeam and others, . . 5 



There is a complete crop of acorns every six to eight years, and 

 the reproduction of oak is favoured by removing beech in the 

 thinnings and seeding fellings. The oak attains large dimen- 

 sions, one tree I measured being 133 feet in height, with a girth 

 of 14^ feet at chest-height. Reproduction of the oak is so good 

 that only 2 per cent, of the felling areas has to be planted 

 with it. 



On the lowlands below the forest, which are less well drained, 

 the hedgerows are full of pedunculate oak, showing the different 

 stations assigned by nature to these species. 



Beech. — Beech forms about one-third of the standing crop. 

 When the Tir et Aire system was in force, owing to the absence 

 of thinnings, beech tended to supplant the oak, especially as the 

 rotation was then 150 years, instead of 200, as at present. Even 

 when the present system was first introduced, as the reproduction 

 areas were not carefully treated by cutting away sallow, birch, 

 and beech, which tended to suppress the oak saplings, beech 

 became too numerous ; but this is no longer the case, as in the 

 cleanings and early thinnings the beech and softwoods are cut 

 out and lopped, in order to protect the oak from their shade. 



Beech trees, when isolated in the seeding fellings, get sun- 

 blistered and become stag-headed ; but in the mature woods, 

 they occur 130 feet in height and 10 feet in girth. 



Hornbeam. — Hornbeam is found disseminated throughout the 

 forest, and forms about one-twentieth of the crop. It is useful in 

 filling up thickets of young oak, and being less vigorous than the 

 beech, is not so dangerous to the oak. 



Scots pine. — This species has been planted pure on all the 

 sandy areas, and forms about one-tenth of the whole crop. The 

 pine poles are now about forty-five years old. 



