CRAIB—REGIONAL SPREAD OF MOISTURE IN WOOD OF TREES. II 
shown by the leader some little distance behind the top of the 
crown not completing its storage until well on in the season. 
If expressions regarding the sap are to be used, they must be, 
in view of what I have shown, some such as “ the sap is in ”’ or 
“the sap is out.” 
During the felling season, then, trees with very varying 
moisture distribution are being cut down. At the beginning of 
the season the centre of the tree is very wet, at the end of the 
season there is a very wet region almost on the outside and the 
centre is very dry. Between these two extremes there are all 
the intermediate stages. Which is the best condition from the 
point of view of the seasoning of the timber ? 
Are not the main reasons for winter felling of deciduous 
trees simply : 
1. Custom. 
2. Availability of labour. 
3. Absence of leaves overhead and consequent light pene- 
tration. 
4. Damage to undergrowth reduced to a minimum, and 
5. The slower seasoning of the timber and risk of cracking 
reduced to its minimum ? 
There is in this country a deeply rooted prejudice against 
summer felling. Asked his reasons against summer felling, a 
forester will usually give his individual interpretation of “ the 
sap is then up.” This expression has already been dealt with 
and no longer holds as an argument against summer felling. 
Though undoubtedly there is a greater supply of labour avail- 
able in the winter, labour has no bearing on the present question 
and cannot be treated of here. Long-established custom can, 
I am afraid, be changed only by necessity. But in the present 
times even this deep-rooted custom has had to yield, at least 
in many cases. Kiln-seasoning has now been so far perfected 
that, according to some authorities at least, the quality of the 
timber is in no way reduced by the artificial method. Does 
the distribution of the moisture at the time of felling afiect 
in any degree the successful artificial seasoning of the timber ? 
The first stages of the artificial method may be regarded as 
providing a safeguard against any defects which might otherwise 
arise from inequalities of moisture distribution in the untreated 
timber. 
There is one other way of regarding the results of the present 
investigation with respect to the popular opinion on sap i 
tribution. Trees at the commencement of the felling season 
are very wet in the centre, at the extreme end of that season 
the bulk of the moisture is on the outside, and during the season 
there are all the intermediate stages between the two. 
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