fj 
* 
| (on 8, Bain, No. Lxv1, Jannary 1923.) 
Regional Spread of Moisture in the Wood 
of Trees. III. 
BY 
WILLIAM GRANT CRAIB, M.A., 
Regius Professor of Botany in the University of Aberdeen. 
With Plates CLXXX-+CXC. 
[. Sparta gta ed Trees meh g the Period late Autumn to 
atly Spring (Contd.). :. 
IT 
Deciduous-Leaved Trees during the Veitene Period. 
a. Bud opening and hid pe J Phase. : 
b. Full-leaf conditio 
III. Evergreen Broad-Leaved ied 
IV. Coniferae. 
V. Wind as an Agent in ‘Ries Shee: 
PU UO! 
“Iu wm ww 
I. Deciduous-Leaved Trees during the Period late Autumn 
to Early Spring (Contd.). 
AN earlier paper* summarised the results of experiments on 
the moisture content of the wood of newly felled trees of Acer 
Pseudoplatanus at various times during the leafless period. Up 
to that time only two species of true heart-wood trees had been 
examined, viz. Ulmus montana and Quercus cerris. From the 
one spetimen of each that had then been examined it was possible 
to say} merely that the results obtained were comparable with 
those for Acer and to suggest that in all probability true heart- 
wood trees would be found to be similar to Acer in their behaviour 
as regards moisture-spread throughout the entire leafless period. 
Subsequently a series of trees of Ulmus was examined in 
exactly the same way as that of Acer, the months of felling being 
October, November, January and March. The general results 
were exactly as predicted. Moisture storage takes place in the 
heart-wood in the end of the year and this moisture travels out- 
wards as the season progresses. Slight differences of detail when 
compared with Acer were observed but these in no way affected 
the general results and in the present state of our knowledge I 
* Notes Roy. Bot. Gard. ae vol. i No. LI. p. 1 (2938) ; for second 
