THE LARCH AND ITS IMPORTANCE IN SWEDISH FOREST ECONOMY. LXXIX 
the Japanese larch, in which is first treated its requirements in soil and climate. 
This larch can with advantage be cultivated on the three best qualities of 
ground in Sweden, while, on the other hand, especially dry places should be 
avoided. On the cultivation of this larch in Sweden it has been found that 
it is easily affected by the frost during its first years. 
After this is treated, on pp. 767—768, the cultivation of the species. As 
the Japanese larch is more tolerant of shade than other species of larch, it 
can be planted closer than these without taking any harm. In England it is 
often set out at a distance of intervals of 1:2 m. On the other hand, it 
closes up very rapidly in its youth because of its rapid growth, and so an 
interval of 1.5 m may be sufficient. 
The Japanese larch should preferably be planted in pure stands. It can 
possibly be used with advantage to fill up small gaps of regrowth of other 
kinds of trees, as it is not so exacting of light as the ordinary larch. 
Like all species of larch, the Japanese larch ought to be thinned early 
and heavily. Nevertheless thinning may be delayed somewhat longer with 
this larch than with the European larch. The risk of getting weak oppressed 
trees, which are early attacked by canker and thereby become infectious, 1s 
somewhat less than with the other species. Moreover, as this larch has a 
great propensity to become crooked and to throw out large branches (see 
Fig. 102), it may be advisable that the trees should keep each other in order. 
In Sweden, therefore, it need not be thinned until the age of 20: possibly 
on ground of qualities II—III it may be postponed till the age of 25, but 
not longer. As to the thinning yield we have as yet no experience in Sweden, 
and reports on this subject from other countries are extremely scanty. 
After this are treated the increment and productivity of the Japanese 
larch. A summary, following HOLLAND (54r), is given of its development in 
Wirtemberg on Pp. 769; and KUMÉ's productivity table (552) is summarized 
on the same page. 
As the sample-plot material for the Japanese larch from Sweden is too 
small and too young, it has not been possible to make any direct summary 
of this point. With regard to the Japanese larch we also know, of course, 
that its height-inerement in youth is extremely rapid, but that later this drops 
off very considerably. It has therefore proved impossible to make use of the 
Swedish Japanese sample plots in the comparative survev that has been made 
of the productivity of European and Siberian larch. A glance atthe Japanese 
productivity-table also shows a very rapid rise in the height-inerement during 
the first decennial periods, far exceeding that of the other species of larch. 
A comparison between the scanty Swedish material and the Japanese pro- 
ductivity-table shows that the young eleven-year old plot at Skärsnäs falls far 
short of Japanese ground quality III. The fourteen-year-old plot on Hallandsås, 
on the other hand, is of about quality III, as also are the seventeen-year-old 
plot on Visingsö and the little larch stand at Båstad. The above cited plots 
from Wirtemberg also correspond to the larch quality III of the Japanese. 
All this is based on the height. It is very striking, on the other hand, how 
small the mean diameter and the volume are in the Japanese stands. 
The agreement between the Visingsö plot and the nineteen-year-old stands 
in Wirtemberg, however, is very striking. : These plots show, in the seventeen- 
