268 PLANT DISEASES 



ing as for brown rot usually controls this trouble. If it appears, 



spray with lime sulfur, 1-40, or dust heavily with powdered sulfur. 



I^AF-si'OT {("i/lindrosporiuni padi). — A fungous disease in which 



the leaves become thickly spotted with reddish or brown spots and 



fall prematurely. The spots often droi) out, leaving shot holes. 



Control. — Spray with lime sulfur, 1-40, or with bordeaux 



mixture, 4-4-50, as for brown rot. 



WiNTEU Injliiy. — Trees so injured make a scant growth; many 



leaves turn yellow and fall about picking time; gum exudes at the 



crotches and about the trunk; sometimes the bark on the stock is 



entirely killed, in which case the tree languishes and finally dies. 



Conlrol. — It is thought that heavy applications of highly nitrog- 

 enous fertilizers in late summer favor winter injury. Do not 

 stimulate the tree to too active wood development. Cut out the 

 gum pockets and cankers, and paint them with a heavy lead paint. 

 Chestnut. B.\rk Disease {D iapor the parasitica) . — A fungous disease, 

 attacking the bark of the American chestnut. Limbs and trunk 

 are ginlled, and the tree dies. The disease is present in many of 

 the nurseries. 



Control. — Inspect nursery stock very carefully, especially 

 about pruned stubs. Discard diseased trees. Make a careful 

 examination of old trees, especially about old wounds and pruned 

 stubs. If the disease is present, clean out the diseased wood with 

 a gouge, and coat heavily with gas-tar. If the disease has pro- 

 gressed far, cut off diseased limbs or the whole tree and burn at 

 once. Keep all wounds and pruned stubs covered with gas-tar. 

 Chrysanthemum. Leaf-spot {Septoria chnjsanthemi). — First ap- 

 pears as dark brown spots, which increase in size until the leaf dies. 

 Control. — Pick and burn diseased leaves. Spray the plants 

 with bordeaux mixture, 4-4-50. 

 Rust (Puccinia chrysanthemi). — Reddish brown rust pustules on 

 the leaves. 



Control. — Avoid wetting the foliage when watering. Spray 

 JUS for Leaf Spot. 

 Corn. Iv\u-R()T (Diplodia zecc). — Several other organisms may cause 

 an ear rot, but this is the more connnon one. The ear is imper- 

 fectly developed, soft, and overrun with a whitish mold. In 

 many cases the husks and silk are also involved. 



