Fungous Diseases of Garden Plants. — 145 



soil, as suggested by Dr. Halsted, may be tried. A spinach leaf 

 spotted with mildew, is shown in accompanying illustration (re- 

 produced from Gardening). Other 

 diseases of the crop, the leaf 

 blight, white smut, etc., may be 

 treated in same way. 



Diseases of Sweet Corn. — 

 " Corn sjnut" is so widely dis- 

 tributed, and so generally known 

 to every soil tiller that a descrip- 

 tion here will not be required. 

 The fungus can live in the soil 

 from year to year. Infection 

 should be prevented by the early 

 and complete destruction of all 

 smutty plants, and the use of new 

 and uninfected soil. There are 

 still other diseases of the corn 

 plant, but they seldom cause much 

 anxiety or loss to the gardener. 



^-m 



Spinach Leaf Spotted with 

 Mildew. 



Diseases of the Sweet Potato. — Several kinds of rot 

 attack the sweet potato. The ^' black rot'' has been found quite 

 prevalent and destructive in the Atlantic coast States, frequently 

 destroying twenty-five per cent, of the crop. Dark, somewhat 

 greenish spots, varying from a quarter inch to four inches in 

 diameter, develop on the tubers, sometimes covering the greater 

 part of the surface, and extending some distance into the tissue. 

 The injury takes place mostly after the potatoes are stored. To 

 prevent it, use only perfectly healthy seed or plants, destroy all 

 infected vines and refuse roots by burning, and practice strict 

 rotation. Commercial fertilizers will be found safer for this crop, 

 in this respect, than large quantities of stable manure. The 

 proper treatment of the tubers in storage is as yet a matter for 

 experiment. 



Diseases of the Tomato. — The ''tomato rot" is a common 

 and often destructive disease. A small blackish spot appears at 

 the blossom end of the half-grown fruit, increasing in size with 

 the growing tomato, and rendering it entirely worthless. The 

 older (less improved) varieties, like Trophy, the small cherry and 

 plum sorts, etc., are seldom affected by this disease. Training 

 the plants, thus exposing them to air and sun, and spraying with 

 fungicides seem to lessen the tendency to rot. 



The '' winter blight" is a malady of greenhouse tomatoes. 

 When first attacked, the leaves become dwarfed and somewhat 

 faded, with indistinct yellowish spots on tlie surface. The spots 



