220 MANUAL OF GARDENING 
up with great luxuriance during the summer, giving a dense 
screen and presenting a semi-tropical effect. For such purposes, 
the roots should be planted only two or three feet apart. If, 
after a time, the roots become so crowded that the shoots are 
weak, some of the plants may be removed. Top-dressing the 
area every fall with manure will tend to make the ground rich 
enough to afford a very heavy summer growth. (See Fig. 50.) 
The making of hedges. 
Hedges are much less used in this country than in Europe, 
and for several reasons. Our climate is dry, and most hedges 
do not thrive so well here as there; labor is high-priced, and 
the trimming is therefore likely to be neglected; our farms are 
so large that much fencing is required; timber and wire are 
cheaper than live hedges. 
However, hedges are used with good effect about the home 
grounds. In order to secure a good ornamental hedge, it is 
necessary to have a thoroughly well-prepared deep soil, to 
set the plants close, and to shear them at least twice every year. 
For evergreen hedges the most serviceable plant in general is 
the arbor vitse. The plants may be set at distances of 1 to 24% 
feet apart. For coarser hedges, the Norway spruce is used; 
and for still coarser ones, the Scotch and Austrian pines. In 
California the staple conifer hedge is made of Monterey cypress. 
For choice evergreen hedges about the grounds, particularly 
outside the northern states, some of the retinosporas are very 
useful. One of the most satisfactory of all coniferous plants 
for hedges is the common hemlock, which stands shearing well 
and makes a very soft and pleasing mass. The plants may be 
set from 2 to 4 feet apart. 
Other plants that hold their leaves and are good for hedges 
are the common box and the privets. Box hedges are the best 
for very low borders about walks and flower-beds. The dwarf 
variety can be kept down to a height of 6 inches to a foot for 
