372 Report of the Horticulturist of the 



grow with the beans, and appears on the stems and seed-leaves as 

 almost black spots of variable shape and size. These rapidly enlarge 

 and may eat into the stems so as to entirely destroy the yomig seed- 

 lings. When the infested plants are not destroyed in this way they 

 continue to grow and spread the infection to neighboring plants. 

 The disease attacks the under side of the leaves, causirig dark spots, 

 and shriveling and discoloring the veins and midribs. The damage 

 which usually attracts most attention is that done to the pods and 

 beans themselves. On the pods, small dark pits are formed with 

 brown or red borders At first small, they rapidly enlarge and be- 

 come large irregular pits. When thus attacked, the pods are unsala- 

 ble as snap beans, and the discolored beans are unfit for either mar- 

 ket or seed. 



Remedy. — The following recommendations for treating this 

 disease are based on experiments conducted on the Station grounds.^ 



It will pay to pick over the beans so that no diseased seed shall 

 be planted. 



After the seed has come up, go over the rows and pull up all of 

 the diseased seedlings and destroy them. If they are left lying on 

 the ground the fungus will mature its spores and thus continue the 

 spread of the infection. 



About the time the plants have put out the third leaf, begin 

 spraying with Bordeaux mixture, 1 to 11 formula. The method 

 of preparing this mixture is explained in article 4 on Fungicides 

 and Insecticides. Spray again when enough more foliage has grown 

 out to justify another treatment. Probably three or four treat- 

 ments at least will need to be made. Whether this treatment will 

 make the bean fodder harmful to stock is a point that has not yet 

 been investigated. 



Wet weather is favorable to the development and spread of the 

 disease. In infested fields the beans should not be cultivated when 

 wet with rain or dew lest the germs of the disease be distributed 

 rapidly and widely in this way. 



Weevil. — Dried beans are frequently found to be infested with 

 the weevil, a small dark gray beetle that appears in the spring, many 

 times being carried to the fields in the seed. The eggs are laid in 

 the young pods. If the beans are picked while green, the eggs or 

 larvse are, of course, destroyed, and no damage is done. When the 



9 See Bulletin No. 48, Dec, 1893. 



