Clare Island Survey — Tree- Growth. 9 7 



the root. The Oak stumps in this group were smaller on the whole. Several 

 logs were found, about 10 feet in length, and quite straight, with mean 

 diameters of 9 to 12 inches, while west of Lough Avullin several large Oaks 

 had recently been dug out, about 15 feet in length, and at least 18 inches in 

 diameter at breast-height. The age to which the trees had attained varied 

 from 100 to 200 years, but the sapwood of most having decayed away, many 

 rings had disappeared. 



The depth of the peat now remaining seldom exceeds 6 feet, and the 

 stumps usually occur in definite layers about 2 feet above the water-table, 

 the upper part of the bog having been cut away in all cases. 



Another group of bogs with tree-stumps is found in the circular depression 

 lying between Curraghmore and Lough Avullin, and due north of Creggan. 

 These bogs lie in small depressions in the surface, which here slopes gradually 

 from the cliffs on the north-west side of the island towards the south and east, 

 and are more or less mixed up with mountain peat in the slopes and higher 

 ground. These marsh bogs are smaller than those on the lower group, 

 and lie from about 200 to 400 feet above sea-level. The stumps found in 

 this group were all Oak, Birch, Willow, &c, and no trace of Pine was found, 

 except one stump north of the path below Knocknaveen, and apparently 

 about 350 feet above sea-level. The Oaks here were quite up to the 

 dimensions of those found lower down, the end of one projecting from a 

 peat-bank having a diameter of 13 inches. Most of these Oaks were rooted 

 in a foot or more of peat, and were in definite layers, as in the case of the Pine 

 stumps at lower levels. 



The partial or total absence of the Pine from this group is difficult to explain, 

 unless one can suppose that when Pine grew at the lower levels the climate 

 was too cold to allow tree-growth on the higher parts of the Clare Island area. 

 If this were so, however, it must have been followed by warmer conditions 

 when the Oak came in, and any improvement in the climate would benefit the 

 Pine to an equal degree, and enable it to grow at any elevation attained by 

 the Oak. It is more probable, therefore, that the absence of Pine is connected 

 with the period of peat-formation, and may possibly be explained by the 

 formation of the mountain peat and the smaller marsh bogs after the Oak had 

 thoroughly established itself, and the Pine had become comparatively scarce. 

 If this were so, the stumps of the earlier generations of Pine would have 

 decayed in the ordinary way, and left no trace behind. It is possible, of course, 

 that more Pine stumps than the one seen exist on this area, but an old and 

 intelligent islander, who was questioned on the subject, could not remember 

 any " bog dale " being seen on that part of the island, although he was well 

 versed in the various localities in which the Oak was found. One must 



