58 
95 Diseases of the Larch. According to 3Ir, Stephens of Edin- 
burgh, who has addressed a letter to De Candolle upon the sub- 
ject, the Larch, Larix Europaea,is subject, in Great Britain, to two 
diseases. The first disease consists in the decay of the heart of 
the wood. It occurs not only in wet situations, but also in dry 
places, as in Nottinghamshire, where immense losses have been 
sustained. It has only manifested a slight appearance at Dun- 
keld, and is most prevalent in England. The Larch has been 
found not to thrive, where Scotch fir, Pinus Sylvestris, has pre- 
viously existed; but this is not the cause of the disease. Another 
disease to which it is subject, is a blister, which forms about two 
feet above the ground. These blisters are produced on two sides 
of the tree, alternately, until they reach the top, when the tree 
dies from above, downwards as it were. Sometimes the blister 
surrounds a branch, which breaks off in the course of time. This 
accident is frequently ascribed to the weight of snow. The range 
of this disease is at present bounded by the county of Forfar, and 
the south of the Grampians. It attacks entire plantations, but 
rarely trees above 25 years of age, and is most destructive in 
poor soils, or on hard formations, as clinkstone. None of the 
Dunkeld trees, at an elevation of 1000 feet, have been affected. 
De Candolle states, that on the Alps, the Larch is free from any 
disease, save the occasional loss of its leaves by the attacks of a 
caterpillar, and a resinous blister or canker, which however, pro- 
duce no injurious effect upon the tree. It grows extremely well 
at Moritzburgh, near Dresden, in a moist sandy soil, 238 feet 
above the sea. He proposes, for this country, the following re- 
commendations: 1. That the higher parts of the country are 
best suited for its growth, provided that the ground be not too dry, 
nor hard, nor marshy. 2. That the sides of the hills are better 
suited for it than the summits; and if the summits are marshy, 
the inferior parts of the mountains will be proper for it. 3. It is 
remarked on the Alps, that the Larch succeeds better in a north- 
ern than in a southern exposure. The difference is sometimes so 
striking, that in vallies running from east to west, it is not un- 
common to see the side exposed to the north, covered with Larches, 
and that exposed to the south, with scarce a tree. This may be 
ascribed to the irregularity of the spring, but will not apply to 
this country. 4. The plantations of Larch in this country are 
too thick, the trees being generally planted at a distance of 3 or 
95, Records of Science.— Translated from Bibliotheque Universelle. 
