466 DISEASES OF ECONOMIC PLANTS 



remaining foliage sprayed with Bordeaux mixture. The 

 disease is strictly local, and close attention will stop its 

 spread, even after it has attained considerable foothold. 



Completoriose {Completoria complens Lohde). — Upon 

 sporeUngs (prothallia of aspidium and pteris) this dis- 

 ease is first shown by a yellow or yellow-brown color, 

 as seen in mass. Under a hand lens the abnormal color is 

 seen as spots, varjdng from green to yellowish brown and 

 later to black. In later stages disintegration of the af- 

 fected cells gives the prothallia a ragged appearance. 



GOLDEN GLOW 



Powdery mildew {Erysiphe cichoracearum DC). — This 

 is a characteristic powdery mildew. 



HOLLYHOCK 



Rust {Puccinia Malvaceanim Mont.). — This rust, native 

 to ChiU, was introduced into France about 1868. It 

 spread rapidly over all Europe, from whence it came to the 

 TJnited States about 1886 upon infected seed. It was 

 rapidly disseminated throughout this countrj', and is 

 now known from Maine to Louisiana, in many places 

 rendering the plants unsightly. It is easily recognized by 

 its yellow to brown sori, each sorus considerably raised 

 above the surface of the leaf or stem as a small, wartlike 

 protuberance. Badly rusted leaves, or even whole plants, 

 wither and die as though blighted. In mild cases the 

 leaves remain green and the plant may bloom. 



It is recommended to sponge the diseased parts with 

 permanganate of potash: two tablespoonfuls of saturated 

 solution diluted with one quart of water. 



