THE GIRTH-INCREASE OF TREES, 63 
narrowest part, four feet two inches above ground, as Sir Robert 
Christison ascertained its rate to have been 1:20 for the three 
years before the first decade, and in the first year of that decade 
it grew 1:00. It then encountered the three hard winters, in the 
two first of which the rate fell to -4o and -30, and it never after- 
wards rallied to above ‘80; the average rate in the first decade 
being ‘60 and in the second ‘48. Notwithstanding this pro- 
gressive decrease, the tree is still handsome and_ healthy 
looking, with a girth of above seven feet at four feet above 
ground, and nearly ten feet at the base. 
ROBINIA PSEUDACACIA. 
a 3 ANNUAL INCREMENTS. 
| Apa Ann | Giet 
lS iee Total. “Ay. so 
et E st, 
s Decade} iggg. 1882. | 1890, | 1891. | 1892. 4 1893. | 1894. | 1895. | 1896. | 1897. “s 
14 3 | pect ois | eee 80-275) 85 F140 4 106 | 85 560) ‘93 | 11-90 
This very young tree is thriving well in the North border of 
the Arboretum. It was but slightly pruned in 1895, so I have 
included the two following years’ results. The rate, compared 
with other infant trees, seems good, as it is barely a foot in 
girth, and has increased nearly at the rate of an inch a year for 
six years. The growth was progressive, from ‘60 to 1°40 for 
four years, but has declined to ‘95 in the next two years. 
CRATAGUS OXVACANTHA. 
a ge ANNUAL INCREMENTS. ees 
5 1st ; Total.| $a 
S |Pecade, ises, | 1889. | 1990. | 1891. | 1892. | 1893. | 1894, | 1895. | 1896. | 1897. 
16; 45 | 60 | 65 | 65°| “45 | 0] 05 | 35 | 05 | “10 | 05 | 3:86| 46 | 47°55 
19 1:05 | 165 | 95 1100/1201 -45| 50 /| 85 | -10| -20 | 765| ‘96 | 10°40 
u 100 f1t0 | #6} 110) 20 | 25 | 406/101 | 14-48 
The handsome Hawthorn, No. 16, at the East walk of the 
Garden, grew at the rate of a little above half an inch in the 
first decade, and attained a girth of above three and a half feet. 
