1887-88.] Annual Increase in Girth of Trees. 



247 



A. Deciduous Trees. 

 Betula alba. 



No. 

 in 



List. 



Girth 

 when 

 first 

 mea- 

 sured. 



55-40 

 56-20 



Annual Increments. 



1878187918801881188218831884 1885 1886,1887 



0-25 



0-05 0-05 

 ... -40 



0-10 



0-10 0-00 



•45| -45 



0-10 

 •45 



-0-05 

 ■40 



Girth, Total 

 Oct. In- 

 1887. crease. 



0-10 0-00 56-05 



45 -50 59-85 



0-70 

 3-65 



Aver- 

 age 

 annual 



In- 

 crease. 



0'07 

 0-45 



The results for this species, as a whole, are rendered 

 nugatory by the complete break down of IS'o. 1. 



This weeping birch, transplanted from the former Botanic 

 Garden, and long a chief ornament of the present one, was 

 first measured in November 1874. In the three follow- 

 ing years its girth increased at the annual rate of 0'41, 

 but in 1878 the increase dropped to 0-2 5, and although 

 the tree still retained a handsome and healthy appearance, 

 it had probably passed its prime. Then came the three 

 consecutive disastrous seasons, which completely checked 

 the growth. Eapid degeneration ensued, and now not half 

 the proper proportion of foliage remains. The table shows 

 the apparently deadly effect of these seasons upon the girth 

 increase, which in nine years amounted in all to barely half 

 an inch. 



No. 5* is a fine healthy tree of the same size as No. 1. 

 It was first measured in 1880, so that the effects of the 

 se^'ere seasons upon its girth-increase cannot be precisely 

 ascertained ; but apparently it was little affected, and the 

 increase has on the whole been exceptionally steady. 



In the spring of 1880 this tree was noted as being in full 

 leaf so early as the 1st April ; on the other hand, in 1886 the 

 buds had not begun to open on the 1st May, yet the increase 

 in the two seasons was nearly the same. The variation in 

 its annual increase has been remarkably small, ranging 

 between O'oo and 0'40. 



Fag us sylvaiica. 



Of all deciduous trees the beech attains the greatest 

 perfection throughout Scotland in general, and the neigh- 

 bourhood of Edinburgh is no exception to the rule. For 



