146 LANDSCAPE DESIGN 



which they contain can be kept damp, — obviously a difficult matter 

 with the shallow soil which runs out upon a rounded bowlder. Natu- 

 ralistic rockwork of this kind offers the further advantage that it can 

 be laid up at a steep slope or even with an overhanging face, without 

 necessarily sacrificing its natural appearance. And a proper choice of 

 the rock material, when this is possible, so that it shall have a definite 

 stratification and cleavage (see Plate 27), and an arrangement of the 

 rocks, here simulating a solid ledge, here closely grouped, here scat- 

 tered, but always suggesting the parallelism of the strata, will be a 

 powerful aid both to the unity and to the naturalness of the design. 

 The designer need not be driven into too great uniformity by thus 

 expressing the stratification of the supposed ledge outcrops. In nature 

 the smaller pieces dislodged by frost may be thrown into any position. 

 At the foot of a steep face of rock, for instance, there may be a talus- 

 / slope, a jumbled pile of dislodged fragments. Some study in the ar- 



rangement of these more accidentally-placed smaller pieces will give 

 sufficient variety without sacrificing naturalness. 



It is possible, where the scale of the design is large enough, to com- 

 bine ledge outcrop and stream-cut bowlder bank and perhaps gravel 

 and sand deposit in one composition, but it should not be attempted 

 unless great care can be given to the actual execution, to keep one 

 character dominant in each scene, for unity of effect. 

 Color and In all designs of rock, whether in ledge or in bowlder bank, the 



<?^|Mr<? 0/ texture and the color of the rock are very important. The rock nor- 



mally gives an effect of strength and solidity in the design, and for this 

 it does not need bright color. It is rarely desirable therefore to have 

 the color of the larger rocks and ledges very conspicuous. Moreover, 

 to give an appearance of age and so of naturalness to the design, 

 weathered or lichened rocks should be used if possible. A light colored 

 rock is likely, in most localities, to look as if it were newly exposed to 

 the weather. A rock dug from beneath the ground will retain for years 

 an unnaturally bare appearance which makes it very hard to deal 

 with in this sort of design. It should not be forgotten, however, that 

 some mosses grow only in shade and dampness, and some lichens best 

 in sun. If they are to persist, the rocks on which they grow must be 

 used in situations similar to those from which they came. 



