290 
OTIS F. CURTIS 
were a bright green. At the same date, May 6, there were no apparent 
differences in the growths of stems not ringed and of those ringed back on 
the 5- to 15-year-old stems. On May 25 measurements were made of 
these stems. An average of the shoots of ten stems of this series showed a 
growth of 9.96 cm., while that of the corresponding check stems was 11.09 
cm. The older stems, whether the diameter was large or small, showed 
growth fully as great as that of those not ringed, but some of the younger 
stems showed somewhat lessened growth which lowered the average for 
the growth of ringed stems. In most cases growth had ceased and ter- 
minal buds were beginning to develop at the time of measuring. 
On April 7, a number of stems of a pear tree growing in sod were ringed. 
These stems ringed in the one- and two-year-old wood showed distinctly 
lessened shoot growth, but those ringed where the diameter was from 1.5 
to 3 cm. showed growth fully as great as that of the unringed stems. 
On May 16, 1919, stems of an apple tree that was just beginning growth 
were ringed just below the base of the one-, two-, and five-year-old wood. 
At the time of ringing, the lengths of the shoots measured to the tips of the 
infolded leaves were from 1.5 to 2.0 centimeters. At the same time a 
single branch was ringed at its base where it measured 3.8 centimeters in 
diameter. The diameter of the main trunk just below the lower limbs 
was II. o centimeters. All the stems ringed in the fifth-year wood (group 4) 
were less than one centimeter in diameter at this point, with the exception 
of those lettered c and j which were respectively 1.2 and 1.5 centimeters in 
diameter. The growth was completed in most of the twigs when the 
measurements were taken on June 15. These data are recorded in table 3. 
Table 3. Pyrus mains. Ringed May 16, IQ19. Measurements taken June 16. All 
of the same letter excepting in column 5 were closely matched. Column 5 and letters a to h on 
one tree, i to n on another. The data are represented as growth in centimeters. 
I 
Not Ringed 
Ringed Below 
Base of One-year-old 
Wood 
3 
Ringed Below Base 
of Two-year-old 
Wood 
4 
Ringed Below Base 
of Five-year-old 
Wood 
b 
Ringed at Base of 
Branch 3-8 Cm. in 
Diameter 
a 
17.5 
I.O 
4-5 
II-5 
12.5 
h 
14-5 
0.7 
•5 
5.0 
13.0 
c 
9.5 
0.4 
3.0 
ICQ 
13.0 
d 
15.5 
0.4 
2.0 
9.0 
12.5 
e 
17.0 
*3.o wound healed 
6.0 
21.0 
10.5 
/ 
g 
16.0 
1.0 
II-5 
10.5 
*5-5 wound healed 
3.5 
10.5 
h 
lO.O 
2.5 
*i.5 broken 
14-5 
*2.5 wound healed 
6.5 
lO.O 
i 
19-5 
0.4 
4-5 
13-5 
17.5 
1-5 
6.0 
/ 
18.5 
1.8 
7.0 
m. . . . 
17.0 
*6.5 wound healed 
3.5 
n 
14-5 
*3.o wound healed 
4.0 
9-5 
Ave. . 
15-14 
1.08 
4.42 
11.15 
12.3 
* Not included in average. 
