GENERAL SUMMARY 191 
special attention should be given to the survey of recently 
felled areas, as in such situations infected localities can be 
more exactly determined, and may be dealt with more 
successfully. Lastly, where fructifications are abundant, it 
is worth while to cut them down with a scythe or sickle, 
as once they are cut through they have little chance of 
spreading their spores. 
About needle diseases the predispositionist can have 
little to say, since there is no reason to believe that the 
needles borne by robust trees are in any way less liable to 
attack than their weaker fellows. The only needle disease 
which need be seriously feared, outside the nursery, is the 
needle-cast, Sphaerella laricina, which may become epidemic, 
especially where larch is mixed with spruce or other ever- 
green. Where such mixed woods are attacked by this 
disease for many years in succession it is worth while to 
thin them out and to remove one or other species entirely. 
If it is decided to keep the larch, underplanting with beech 
is calculated still further to lessen the damage inflicted by 
the disease. 
The fungi that attack nursery lines of larch are chiefly 
rusts and the damping-off fungi. Rusts may be prevented 
if it is possible to remove the alternative hosts. Damping-off 
should be met first of all by good cultivation of the soil, 
and secondly by spraying or powdering as recommended in 
the section on these pests. 
The long list of diseases to which the larch is liable must 
produce a depressing effect, especially when set out in 
a single story, as in this book. Many of these diseases are 
unimportant, and many are shared by other conifers which, 
in addition, present pathological difficulties unknown to the 
larch. None the less, the larch is more prone to disease 
than any other conifer commonly grown in British woods, 
and the advisability of planting other trees in the place of 
larch has been carefully considered by most foresters. The 
variety of trees introduced from Western America has 
added greatly to the list of species at the planter’s disposal, 
and Douglas fir and Sitka spruce have already been widely 
