SALAD CROP PROJECTS 137 



7. Name five plant foods of the caterpillar other than celery. 



CL : 186. 



8. Describe the adult caterpillar. CL : 186-187. 



Celery is attacked by two blight diseases, one called late 

 blight and the other early blight or leaf spot. The early blight 

 spots first appear on the older or outer leaves as yellowish areas. 

 Later the spots turn brown around the outside and have a 

 whitish center. Varieties differ in their susceptibility to this 

 disease. Spraying with Bordeaux is effective if begun early and 

 should really be started in the seed bed. 



Late blight appears as a leaf spot in its early stages. Later 

 very small black dots appear on the spots and also on the blanched 

 leaf stalks. The leaves sometimes wilt in severe cases. If the 

 disease becomes troublesome, the seeds should be disinfected. 

 Soaking for fifteen minutes, in a corrosive sublimate solution 

 (1 : 1000) is the treatment. This solution is poisonous, must be 

 handled with care, and never used in a metal container. The 

 same seed bed should not be used successively. Spraying with 

 Bordeaux will help to control the disease either in the seed bed 

 or field. 



1. How do the two blight diseases of celery differ in appearance ? 



SH : 174-178. 



2. What three control measures may be practiced to control the 



late blight ? 



20. Harvesting and marketing. — If the crop is to be sold as 

 fast as it is harvested, a convenient plan is to cut the roots a little 

 below the surface of the ground so as to leave a short stub at the 

 base of the plant. No attempt will be made here to describe the 

 numerous methods of preparing the crop for market. It is sug- 



