118 TRANSACTIONS OF ROYAL SCOTTISH ARBORICULTURAL SOCIETY. 
thirty-five years ago almost exclusively with Douglas fir and 
Thuja, which have grown since under forest conditions, and 
rival each other in height and girth. Nevertheless, some care 
should be exercised in planting the Zhuja, for it is liable to 
injury from frost when in a young state, especially on low ground. 
My own experience with it may be of service to others. 
In the spring of 1901 I sowed fifteen shillings’ worth of seed 
of Thuja gigantea obtained from Johannes Rafn of Copenhagen, 
which produced between 50,000 and 60,000 plants. After once 
transplanting, these were fit to put out in the spring of 1904, 
being then 12 to 15 inches high. They were planted in various 
places, among other, 7 acres of flat ground, whence a crop of 
spruce had been removed, were planted solid with them. They 
grew at a great pace during the summer, but in the spring of 
Ig05 came a severe late frost, which killed half of them outright, 
and sorely crippled the rest. Along the south side of this plot is 
a wood about fifty years old on rising ground, screening a strip 
of land from the southern sun. In this strip the ZZuzas hardly 
suffered at all; here, and elsewhere, the shelter of older trees 
saved them, and they are now 3, 4, and even 6 feet high. 
The lesson from this is the same which Mr Munro Ferguson has 
exemplified at Novar, namely, that this valuable tree should be 
used for underplanting older wood. 
Is Rhododendron barbatum INSECTIVOROUS ? 
The buds of Rhododendron barbatum, like those of the horse- 
chestnut, are covered during summer and autumn with an 
exceedingly clammy, green varnish, which hardens in winter 
into a brown coat. Innumerable flies, attracted by the glistening 
buds, settle upon them, and pay the penalty of death. The 
characteristic bristles on the petioles of the leaves, whence the 
plant takes its specific name, assist in the entanglement of the 
larger-winged insects which otherwise might be strong enough 
to escape. Is this indiscriminate slaughter without purpose, or 
does the plant derive nutriment from its mixed bag of victims ? 
Why is this splendid rhododendron so seldom grown? It is 
as hardy as &. ponticum, though its blossoms, of matchless 
scarlet, are apt to be destroyed by the frosts of March. This 
danger may be mitigated if the plant is grown in the partial 
shade of an open wood. HERBERT MAXWELL. 
MONREITH, October 1906. 
