214 FARM GRASSES OF THE UNITED STATES 
and killed. This is especially true on terraces and 
banks where the earth is more easily disturbed, and 
where the sun’s heat falls more vertically at times. 
It is better to water heavily, soaking the ground 
to a depth of a foot or two, than to apply water in 
small amounts and more frequently. On all but the 
smallest plats a sprinkler of the fountain or revolving 
type can be advantageously used. These save a great 
deal of time and labor in applying the water, but care 
must be taken that corners and other small spaces are 
not left without water. 
ROLLING 
Next to the mower the roller is a most important 
implement. It should be used in early spring to firm 
the sward after the heaving of the soil due to freezing 
and thawing in winter. After heavy rains during 
summer and autumn, and on young swards as soon as 
they can bear it, the roller should be used. ‘Those 
made in two or more sections are preferred, because 
they turn with less injury to the soil and sward. The 
most good will be done by the roller weighing at least 
fifteen pounds to the inch of length. One is now for 
sale which may be increased in weight at will by fill- 
ing a hollow compartment with sand or water. 
FERTILIZING OR TOP-DRESSING 
No matter how thorough the preparation, the lawn 
will eventually demand a new supply of food. This 
must be given in the form of natural or artificial fer- 
tilizer. Well-rotted barnyard manure is unexcelled 
for this purpose. It may be applied in the fall and 
