EXPERIMENT STATION BULLETINS. 329 



DISEASE OF THE BEAN. 



ANTHRACNOSE (.Olceosporium lindemuthianum) . 



The spots upon the pods, stems, and leaves of beans, particularly the 

 wax-podded varieties, are commonly called " rust," but are really due to a 

 species of anthracnose. At first it shows as a reddish-brown spot, but the 

 center soon becomes white, finally turning to a light brown. The spots 

 enlarge and if sufiiciently numerous several of them will grow together 

 and cover a large part of the surface of the bean pod or leaf. 



Upon the pods the portion attacked soon sinks below the surface and 

 the disease may spread to the beans themselves, causing them to shrivel. 



The disease is particularly troublesome in damp seasons, or when beans 

 are grown in a low, moist place. If planted upon high well-drained soil, 

 where there will be a current of air, the danger of injury will be lessened. 



The use of copper sulphate solution also seems to prevent the spread of 

 the disease. It should be used very weak, not stronger than one pound to 

 500 gallons of water, and will then do no harm, and with fairly favorable 

 conditions will keep the beans practically free from disease. 



INSECTS OF THE PEA AND BEAN. 

 PEA AND BEAN WEEVILS. 



Although these insects belong to different species and always work in 

 the seed of the one plant which the name indicates, yet their habits are 



alike, and the same treatment will kill one as 

 readily as the other. The eggs are deposited 

 by the beetles on the outside of the pod and 

 when they hatch the young grub, while yet 

 very small, gnaws through the pod, into the 

 young seed and there detelops. The peas 

 seldom contain more than one grub each, 

 ^ & ^Sj^^ I while a single bean may contain as high as 



twenty grubs. It is better not to plant 



"buggy" peas or beans if it can be avoided, 



Fig. 49.- Pea Weevil. Bruchuspisi. gye^ if the weevils are not alive in the seed. 



The germ is not usually destroyed by the weevils, but the seed is weakened 



by the loss of what has been eaten from it. 



Remedies. — Place in a tight jar and use bisulphide of carbon, or 

 immerse in hot water for a few minutes, or place in an oven for a short 

 time and bake them, being careful that the temperature is not much above 

 145 degrees, Fahr. In separating *' buggy " from sound peas, drop into 

 water, when the " buggy " peas will float and the sound ones sink to the 

 bottom. 



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