406 VEGETABLE GARDENING 



549. Diseases. — Onion smut is the most serious dis- 

 ease of the onion. It is likely to become particularly- 

 troublesome when rotation is not practiced. After the 

 land is once infested, this fungus is exceedingly difficult 

 to eradicate. The entire plant may be attacked, and the 

 spores, forming a black dust, are readily disseminated 

 by the wind, insects, and tillage implements. As the seed 

 may also transmit the disease, it is sometimes soaked 

 for about 20 minutes in a solution of formalin (i ounce 

 in I gallon of water), and thoroughly dried before being 

 drilled. No method of soil or plant treatment has been 

 found fully satisfactory. 



Downy mildew (Peronospora schleideniana) , which 

 sometimes appears in warm, sultry weather, causes the 

 leaves to blight. The spores present a downy, violet 

 covering. Timely applications of bordeaux mixture will 

 control this disease. 



PARSLEY (Carum petroselinum) 



550. Importance. — This biennial umbellifer, found 

 wild in the south of Europe, was introduced into the 

 English gardens in 1548. The crop is of limited commer- 

 cial importance in the United States. It is unquestion- 

 ably our most beautiful vegetable for garnishing, but not 

 fully appreciated for this purpose. The leaves are finely 

 cut, curled and valued for salads and flavoring as well as 

 for garnishing. 



551. Culture. — Extra Curled Dwarf is probably the 

 most largely planted. Moss Curled, Fern-Leaved and 

 Summer Green are also popular. 



As the seeds germinate very slowly, they are often 

 sown under glass, and transplanted once before setting 

 in the open. The plants are hardy and may be taken to 

 the open ground nearly as soon as cabbage. It is also 

 customary to sow outdoors early in the spring or at 



