C. M‘INT0SH—NOTES OF A NARURALIST ROUND DUNKELD. 223 
XXII.— Notes by a Naturalist round Dunkeld. 
By C. M‘Intosh, Inver. 
(Read loth February, 1898.) 
The Larch Disease. It is more than 30 years since it was observed 
that the larch was suffering from the attacks of an insect,—I believe an 
aphis,—causing blistering, malformation, and, latterly, destruction of 
the tree. As I am not an entomologist, I cannot say much about its 
life history or the species to which it may belong. During the winter 
months the insects are to be seen in a dormant or inactive state on the 
twigs and branches, especially about the knot-like buds; in the spring 
they become active, spreading over the leaves when these appear. On 
the leaves they deposit a cluster of eggs, each egg attached by a fine 
silk-like thread to nearly the same point on the leaf. The insect, mean¬ 
while, remains in the cluster and partially covers itself and its eggs with 
a white wool-like substance, which it exudes from the pores of its body. 
The appearance of the insect, especially in its dormant state, is like a 
tortoise on a very small scale, very dark brown in colour. Frequently 
there is a small drop of resin in this nest-like cluster. From the 
eggs brood after brood of these insects appear during the summer 
months. The effect of the working of these insects on a larch 
is that much bleeding of resin takes place, the quantity exuded by 
badly infected young larches being so great that a person could not 
pass through a young planting without having his clothes besmeared. 
The stems, branches, and twigs, especially of young larches, become 
deformed with swellings and resin-smeared blisters. On the swollen 
blistered parts a fungus appears,— Lachnella Calycina.^ —a very smsW 
cup-shaped fungus belonging to the Pezizce. Whether it is the fungus 
or the aphis, or both in conjunction, that causes the destruction is a 
question which I cannot answer. In this connection, however, the 
late John Macgregor, who was for many years forester to His Grace 
the Duke of Atholl, maintained that this fungus was only to be 
found on the part of the larch where the insect had been at work, 
and not on dead branches which had been cut from healthy larches. 
In other words, there must be an intimate connection between the 
aphis and the fungus. Tulief classes this fungus as a wound fungus. 
The disease became so serious that the planting of larches on the 
Atholl estate was partially discontinued and much fir was planted 
instead. About twelve years ago, I observed what I thought an 
increase in the number of certain insect-feeding birds, especially of 
the Tit kind, and from observation and enquiries made I became 
convinced that the Great Tit, the Cole Tit, the Blue Tit, the Long¬ 
tailed Tit, together with the Gold Crest, had become much more 
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