IRRIGATION 67 



to get it dry enough to work. Excessive moisture 

 in the soil at the end of the season will invariably 

 produce celery of inferior flavor and poor shipping 

 qualities. 



Irrigation on Muck Soils. On low lying peat or 

 muck soils, it may not be necessary to apply any 

 water in addition to the natural rainfall, but irriga- 

 tion is almost indispensable on clay or sandy upland 

 soils. Muck or peat soils are generally located in a 

 basin or depression of the surrounding soil forma- 

 tion, and by pumping on water continuously the 

 muck will absorb it until saturated and the water 

 will rise almost to the surface. This should be 

 avoided as the soil will become water-logged and the 

 celery plants will be permanently injured. If it is 

 found that sufficient moisture cannot be maintained 

 in the surface soil by frequent shallow cultivation, 

 it may then be necessary to resort to irrigation, but 

 some form of surface irrigation is preferable to flood- 

 ing the muck basin and raising the water table in 

 the soil. The underlying muck, which has not been 

 exposed to the action of the air for centuries, is 

 filled with the acids of decaying vegetable matter, 

 and these acids are injurious to the roots of plants 

 with which they come in contact. 



Methods of Irrigating. There are three princi- 

 pal systems of irrigation used by the celery grow- 

 ers of this country: (i) surface ditches, (2) over- 

 head sprinklers, and (3) subirrigation. Each of 

 these systems has its adaptations and limitations 

 which determine the possibility of its employment 

 under given conditions. 



