THE GIRTH-INCREASE OF TREES. 
53 
This American Oak, on the other hand, seems to excel] the 
native species in its rate. 
At least the young No. 61, after 
fully recovering from transplantation, averaged 1°18 for five 
years, when it became temporarily ineligible from re-trans- 
plantation. 
QUERCUS ILEX. 
2 Ansel ANNUAL INCREMENTS. : 
CAV Ann, | Girth) 
Z| ist Total.| “ay” a 
J |Decade-| 1889, | 1889. | 1890. | 1891. | 1892. | 1893. | 1894. | 1896. | 1896, | 1897 “0 
45} 28 | 45} 40] 60| 85 | 857 70} 15] 20] © 365 | 36 | 47-55 
46] -23 | -40| -40| -45| 30 | -25) -45 | -15| 25] 25] 5 [295] -29 | 34-05 
16 55 | 80 | 86] 50 | 60} 65 | 15| 25] -45 | -35]515| 61] 9°85 
In my paper of 1888 it is remarked that no species suffered 
more from the three severeseasons than the Evergreen Oak. e 
largest in the Garden, upwards of six feet in girth, lost two 
years’ growth of twigs, recovered its foliage slowly and imperfectly, 
some large limbs requiring to be cut off, and has quite lost its 
handsome, shapely form. Nos. 45, 46 did not suffer so badly, but 
their girth-increase was reduced to a mere nothing in 1880 and 
1881. Afterwards they rallied somewhat till 1894, when they 
suddenly failed and almost ceased to grow. No. 45 seems now 
to be dying. It is remarkable that the infant specimen, No. 16, 
in the oak grove of the Arboretum, suffered a serious diminution 
in girth-increase in the same year, so that it would seem that all 
three had been then subjected to some common evil influence. 
The rate of No. 16 in the first quinquennium was no less than 
‘66, although it was a mere infant, girthing only 4°65 inches at 
fifteen inches above ground, when measured at the beginning of 
the period. In the first year of the second quinquennium it 
maintained this average, but in 1894 the rate fell to’15, and there 
has been no full recovery since, so that the rate for the second 
quinquennium has been only °37, or little more than half 
that of the first. At the same time, the tree has never looked 
ill, and it is now a remarkably thriving and vigorous looking 
specimen. 
