Water in Trees under Australian Conditions. 
97 
Eucalyptus globosa: 
Age. 
( a ) Full tree, height 8 yrs. 
6-7 m. Mercury 
applied at tip of 
trunk. 
(<$) Branch of same 3 yrs. 
Length 94 cm. 
Diameter 
Position of 
Length of 
Diameter of 
Average 
Diameter 
of vessels. 
at base. 
longest vessel. 
longest vessel. 
largest vessel. 
8-9 cm. ; 
diam. at 
cut tip, 
2 cm. 
7th and 8th 
years’ wood 
6-i r m. 2 vessels, 
34 vessels at 2-9 m. 
• 137 mm. 
•087 mm. 
Average no. 
of vessels in stem at tip, 8 per sq. mm. 
; at base, 9 per sq. mm. 
1 cm. 
New wood 
87 cm., 10 vessels 
•069 mm. 
•053 mm. 
at 80 cm. 
Average no. of vessels in stem, 60 per sq. mm. 
A few data are appended upon the dimensions of the vessels in the 
Oleander , Ficus , Deeringia , and Tecoma , but in none of these did the vessels 
attain anything like the length shown by single vessels of Eucalyptus and 
Acacia. Experiments have still to be performed on adult trees of 
Eucalyptus 100 feet high or more, but these have been postponed for the 
present, since the work must be done on the spot where the trees grow 
and entails considerable expense. 
Mercury Method. 
Nerium Oleander: 
Age. 
Diameter 
at base. 
Position of 
longest vessel. 
Length of 
longest vessel. 
Diameter of 
largest vessel. 
Average 
Diameter 
of vessels. 
(a) 
Stem (exposed 
tree) 
Stem (shaded 
2 yrs. 
1 cm. 
52 cm. 
•057 mm. 
.038 mm. 
d) 
6 yrs. 
i-2 cm. 
4th yr’s. wood 
75-5 cm. (shaded, 
therefore less active 
•035 mm. 
.021 mm. 
tree) 
transpiration), 26 
vessels at 39 cm. 
Average no. of vessels in stem, 108,500 
Stem (shaded 
4 yrs. 
•9 cm. 
3rd yr’s. wood 
74 cm., 17 vessels 
.046 mm. 
•026 mm. 
tree) at 40 cm. 
Average no. of vessels in stem, 61,236 
As far as these results go they show that the length of the vessels is 
more affected by the age of the stem than by the activity of transpiration, 
whereas the degree of functional use appears to affect their diameters to 
a marked extent, active transpiration favouring an increase in diameter. 
Mercury Method. 
Ficus elastica: 
Age. 
Diameter 
Position of 
Length of 
Diameter of 
Average 
Diameter 
at base. 
longest vessel. 
longest vessel. 
largest vessel. 
of vessels. 
Branch 
t 0 yrs. 
i-8 cm. 
New wood 
47 cm., 20 vessels 
at 38 cm. 
.137 mm. 
•085 mm. 
Branch 2 yrs. 
Deeringia altissima: 
1 cm. 
New wood 
53cm., 25 vessels 
at 32 cm. 
•092 mm. 
•072 mm. 
Branch 
3 yrs. 
• 7 cm. 
New wood 
74 cm., 12 vessels 
at 43 cm. 
.047 mm. 
•032 mm. 
Branch 
Tecoma: 
3 yrs. 
1 cm. 
2nd yr’s. wood 
97 cm., 15 vessels 
at 69 cm. 
•059 mm. 
.004 mm. 
Branch 
3 yrs. 
6 cm. 
48 cm., 8 vessels 
at 28 cm. 
6 
•vr 
3 
3 
.05 mm. 
H 
