Cedars and Cypresses 215 
soils, and are very light-needing; spruces, being shallow- 
rooted, and able to endure only medium shade, require moist, 
not too light soils, and cool situations; firs, being most toler- 
ant of shade, must have deep and well-watered soil, and can 
endure a compact one. The last two mentioned groups, 
being mostly of alpine or mountainous range, must as a 
rule have specially satisfactory soil conditions (depth and 
moisture), in order to stand our drouthy atmospher.. But 
few are adapted to sea-coast condition, or can endure city 
smoke. 
Many species are remarkably immune from diseases if 
placed in proper soils; poorly drained soils, however, being 
apt to give rise to physiological and fungus diseases. Only 
in forests, where large numbers of the same species invite 
multiplication of insects, is there much trouble to be antic- 
ipated from these pests. In their youth some of the species 
are liable to be damaged by, or to succumb to, frosts and 
drouth and since they rely on two to ten years’ foliage, which 
must be replaced, if lost, the recuperation of injured parts 
is often difficult and slow. 
CEDARS AND CYPRESSES 
Under these names, which have been promiscuously applied to mem- 
bers of this group, we can combine several genera of trees which are 
botanically allied and have also much in common as regards aspect, 
form, and behavior. They are characterized by an upright habit of 
branches, a shingle-like arrangement of small, scale-like leaves (except- 
ing Cedrus, Taxodium, and Sequoia), and often by a close stringy bark. 
Having mostly a full supply of foliage, at least when young, they are 
effective in large plantings as accent trees, also in formal plantings as 
individual specimens. 
They are represented in nine genera, namely, Cedrus, Cupressus, 
Chamecyparis (including Retinispora), Libocedrus, Juniperus, Thuja 
(including Biota), Thuyopsis, Sequoia, Taxodium. Most of them, 
especially Chamecyparis, Jumperus and Thuja, have characteristic 
