326 
VEGETABLE GARDENING 
Celery commands a price of io to 75 cents a dozen 
plants. Twenty-five to 40 cents is the usual range of 
prices. Extensive commercial growers regard $100 an 
acre as a fair net profit. Market gardeners usually do 
much better than this. 
416. Insects. — The aromatic flavor of celery seems to 
serve as a repellent to insects, for this vegetable has no 
serious enemy. The following insects are sometimes 
troublesome : Grasshoppers, celery leaf tyer, celery 
FIG. 81. TWO FORMS OF SWISS CHARD 
caterpillar, zebra caterpillar, tarnished plant bug, celery 
looper, carrot rust fly and the little negro bug. 
417. Diseases. — Several diseases of celery are some- 
times serious. The most important are the blights 
(Ccrcospora apii and Septoria pctroselini, var. apii), leaf 
spot (Phyllosticta apii), and rust (Piiccinia bullata). Bor- 
deaux mixture is frequently used for the control of celery 
diseases. Some growers begin making applications in 
the seed bed and repeat at intervals until blanching be- 
gins. The early applications are doubtless most effective 
