618 A HANDBOOK OF CONIFERS 



it is usual to tie all the main branches together. A better method 

 is to shorten the shoots a little now and then, commencing when 

 the plants are young, in order to induce sturdier branches. The 

 Chinese arbor- vitae can be grown as a hedge plant, and stands 

 cutting well. It can be increased by cuttings and by seeds, the 

 varieties by cuttings and by grafting upon stocks of the type. 

 Light sandy loam suits it, but it can be grown on a variety of soils. 

 Some of the dwarf varieties make excellent plants for the rockery. 



Thuya plicata, D. Don. (Fig. 113.) 

 Western Arbor-vit^. 



Thuya gigantea, Nuttall ; T. Menziesii, Douglas ; T. Lobbi, Hort. ; 

 T. Craigiana, Hort. Canoe Cedar ; Red Cedar ; Western Red Cedar. 



In N. America this tree attains a height of 150-200 ft. with a 

 trunk 12-20 ft. in girth above the broadly buttressed base, which 

 is sometimes 50 ft. in girth near the ground. Bark light cinnamon 

 red or brown, ^-f in. thick, divided into wide ridges by irregular 

 shallow fissures, the surface broken up into small plates which are 

 shed irregularly. Branches horizontal, often pendent at the 

 ends ; branchlets in the same plane, much divided, the small 

 lateral shoots falling after two or three years. Leaves on leading 

 shoots parallel to the axis, ovate, long-pointed, each with an 

 inconspicuous resin gland on the back, up to \ in. long, the points 

 free ; those on the ultimate divisions smaller, about \ in. or less 

 long, ovate, short and bluntly pointed, closely overlapping and 

 often without glands, dark green above, usually faintly streaked 

 with white beneath but on some branchlets remaining green ; 

 emitting a tansy-hke odour when bruised. Cones about \ in. 

 long, erect and green when young, reflexed and brown when 

 mature at the end of the first summer ; scales in 5-6 pairs, 

 thin, flexible, with a thickened process on the inner side near the 

 apex and immediately above the thin, triangular, reflexed point. 

 Seeds thin, about \ in. long, winged, 2-3 on each fertile scale. 



The following are the chief variations from the type : — 



Var. atrovirens, Hort. 

 A form very like the type with rich glossy leaves. 



Var. aurea, Hort. 



Leaves yellowish, patches of yellow foliage sometimes occur- 

 ring at irregular intervals over the tree. 



Var. compacta, Hort. 

 Habit dwarf and dense. 



Var. fastigiata, Hort. 

 Habit resembling that of a Lombardy poplar. 



