LXVI GUNNAR SCHOTTE, 
Jesia instead, if the seed can really be guaranteed to have been gathered in 
those countries and, as«regards Scotland, from, let us say, the Dunkeld race, 
Best of all, however, would it be to collect seed from the old, fine, straight- 
growing woods that already exist in this country. 
Finally, the investigations which have been made show distinctly that the 
lareh is one 'of the! trees” that best repays pure race researches; It isfespes 
cially suited for this purpose because of the early age at which it attains seed- 
bearing. 
In chap. III E an account is given of the sylvicultural properties of 
the larch, in which the first point treated is its requirements in growing 
space and climate. Quotations from the literature show what various: 
views have been held in this point. 
The larch loves deep and fresh soil, but not damp ground. As HESSELMAN 
(82, 83) has shown, it has an extremely great capacity for evaporation and is 
able to check the water-logging of forest soil. In spite of its high power of 
transpiration (114, 8368 g. of water per vear for every 100 g. of dry needle ma- 
terial), it makes very small demands on moisture in the soil, which agrees 
very well with its very powerfully developed root-system. The very con- 
siderable material from the sample plots that the present writer has collected 
also shows that the larch gets on well on all moderately good lands in Sweden, 
and that it developes there more strongly than pine and spruce. On the 
other hand, it ought not to be cultivated on the very driest land, as on the 
poor Ose-gravel plateaus or the driest pine-heath areas. 
In its natural area of distribution the larch is insensitive to winter cold 
and is also protected in winter against severe drought. In summer, on the 
other hand, it requires much warmth in order to thrive. It especially likes a 
lasting and uniform warmth, and is consequently a typical tree for a conti- 
nental climate. In order that it may thrive, according to BöHLER (454), it 
seems to require an annual mean temperature from — 1? to + 10? C., and 
plenty of light and abundant circulation of air. It ought to have a winter's 
rest of at least four months and a short spring with a rapid transition from 
spring to summer. In its natural home in the mountain districts it can make 
good use of a very short period of vegetation, since it leafs early, and in 
the Alps sometimes even while the snow still covers the ground. It is ex- 
tremely sensitive to a. great degree of moisture in the air and demands a 
certain degree of dryness in the air. 
The larch is markedly fond of light and is the most exacting of all coni- 
ferous trees as regards light. Its requirement of light is approximately that 
of the birch and the aspen. Consequently natural larch-woods are rather thin, 
and are characterized by a dense grass carpet in Alpine districts. Because of 
the larch's great need of light it may be necessary, when any real care is taken 
of the forest or of the ground, to encourage undergrowth in pure larch forests. 
For this purpose beech is especially suitable; but other trees or bushes that 
bear shade may also be used in regions or on lands where the beech cannot. 
grow. 
Through its very well developed root-system, the larch offers stout resist- 
ance to wind. As the larch has no leaves in winter, it is little liable, as 
a rule, to be pressed down or broken by snow — a fact which has been illu- 
strated by the present winter in a preceding article (194). 
