282 TRANSACTIONS AND PROCEEDINGS OF [Sess. lvi. 



bour, Xo. 85, are low rates compared with other forest trees, 

 but both have every season been well-clothed and healthy, 

 and the range is not remarkably high. The low rates are 

 probably due to the poor soil. 



Xo. 16. Quercus Ilex, although an evergreen, has been 

 added, as it is a Quercus. 0'63 may be too low, as the tree 

 is little more than an infant, its girth where measured, near 

 the ground, being only 7'35. 



b. Range of Girtli-increase in the five years. 



(See Table I.) 



The variations in the increase of a tree in different years 

 may be due to meteorological causes, to variations in 

 health, to passage from the infantile to adult life, or to 

 causes of which we have as yet no knowledge. The range 

 proved always considerable, as the Table shows, but it is 

 comparatively small in Ulmus, 1"50 to I'SO ; Fctgus, 1'15 to 

 1"50 ; and Prunus, 1"15 to 1"45 ; and it is comparatively 

 large in Populus, 0"75 to 1'75 ; Acer, O'TO to 1-55 ; and 

 Cratcegus, 0-70 to 1"G5. 



c. Maximum Annual Growth in tlie Species. 



The last column in Table T. shows that of the seventeen 

 deciduous trees, all of different species, Tilia curopma alone 

 failed to reach an inch of growth in one or other of the five 

 years. None of them attained 2 inches, but Ulmus and 

 Salix were not very far off, with I'SO each. The only decidu- 

 ous tree I have ever measured which grew 2 inches in a 

 year is Quercus confcrta, No. 54, a young tree, but belonging 

 to the older set, which twice in eleven years reached 

 2-05. 



(J. Annual Variation in the atrcreoiate Girth-increase. 



DO' 



As probaljly very few of the trees have attained their 

 maximum rate of growth, it might be expected that the 



