66 A TEXT-BOOK OF GRASSES 



seeds are small and should not be covered deeply. It is 

 important to keep the lawn as free as possible from weeds 

 while becoming established. After the grasses have formed 

 a firm sod or turf, weeds have little chance to intrude. 

 If the soil and the applied manure be free from weed seeds, 

 the task of weeding during the first season will be much 

 simplified. 



85. Subsequent care. The lawn should be frequently 

 mowed, watered, weeded, and rolled if it is to be brought 

 to its maximum effectiveness. If unfavorable circum- 

 stances have caused the death of the grass in spots or if 

 in small areas the grass failed to grow, here the weeds 

 appear later. Such spots should be reseeded. It is much 

 easier to obtain a uniform stand at the first sowing than 

 to patch up afterward an irregular stand. Some weedy 

 grasses make a good appearance early in the season but 

 later die out, leaving unsightly bare patches in the sum- 

 mer. This is true of crab-grass and annual blue-grass 

 (Poa annua). 



86. Watering. Blue-grass lawns usually require for 

 their best development more water than is supplied by the 

 natural rainfall. This is especially true during the dry 

 periods that usually occur during summer. Artificial 

 watering by garden hose is the usual method of meeting 

 the deficit. The water should be applied in the late after- 

 noon or evening as damage may result from watering dur- 

 ing the heat of the day. Water should not be applied in 

 full force direct from the nozzle, as the soil may be washed 

 away from the roots. A spray nozzle prevents this. 

 Thorough soaking from time to time is better than more 

 frequent light sprinkling. Light and frequent sprinkling 

 encourages a shallow root-system, readily injured by 

 drought. 



