CHAP, vii.] WALL-FRUIT TREES. 201 
fill up the places assigned to them, trees of 
inferior kinds may be planted between them, 
so that no part of the wall may be lost—the 
inferior trees being cut in as the others grow, 
and being finally removed. This is accom¬ 
plished by planting alternately dwarf trees of 
the kind which is to remain, and trees grafted 
standard high, which are called riders, of the 
kinds which are to be removed. The dis¬ 
tance at which the permanent trees ought to 
be planted depends upon the nature of the 
tree. 
There is, however, one objection to a 
south or south-east wall for tender plants 
which should be carefully guarded against. 
This is the danger from spring frosts, to 
which the blossoms are exposed during the 
night, from being brought prematurely for¬ 
ward during the day. To guard against this, 
the south wall should have a deep wooden 
coping, supported by holdfasts, projecting 
about a foot from the wall; and under this 
coping there should be a row of hooks, on 
which should be hung a kind of curtain of 
bunting, which should be kept on day and 
night in frosty weather, while the blossoms 
