148 ARMILLARIA MELLEA, 
frequent victim, and after that, according to my experience, 
Sitka spruce, Weymouth pine, and Corsican pine. Larch is 
not usually attacked till it is more than fifteen years old, 
but is then frequently killed by the honey fungus. I have 
also seen trees of deodar, Douglas fir, monkey puzzle, and 
common spruce all killed by it, and probably no species of 
conifer is immune from attack. Among broad-leafed trees, 
oak, beech, chestnut, laburnum, and alder are not infrequently 
destroyed, and I have found a street-planted elm and other 
trees killed by it. Wagner (1899) has found the fungus on 
twenty-nine species of broad-leaved trees in Germany, 
including pear and apple, and in America! many fruit trees 
are fatally attacked. It has generally been held that broad- 
leafed trees do not succumb to the fungus.unless previously 
weakened in some way, but this is always difficult to prove. 
Death does not follow on attack so quickly as in the case 
of conifers, and the early symptoms of the disease may be 
mistaken for inherent weakness in the trees. Certainly oaks 
are attacked in Britain as much in the open as in woods, 
and there can here be no question of suppression by other 
trees. At the same time park trees are especially liable to 
all types of root disease, as for instance beech by Fomes 
australis and F. resinaceus. This is probably due to grazing 
animals damaging the surface roots, and also to the inferior 
quality of the subsoil in parks as compared with woods, for 
reasons mentioned in the discussion on Fomes annosus. 
Larch trees are not usually killed until many years after 
infection. The external signs of advanced attack are the 
death and fall of the needles and generally a flow of resin 
at the base of the trunk. Ifa portion of the bark is removed 
from the tree at a point near the roots, thick white layers 
of mycelium are disclosed, and on digging the soil away 
from the roots rhizomorphs are almost invariably found. 
In woods which have an open canopy the toadstools of the 
fungus may be found growing from the roots of the trees 
for many years in succession before the trees show any 
external symptoms of ill health. 
? Pammel (1911), Horne (1912 and 1914), Hey (1914), Long (1914). 
