BEANS 



BEANS 



211 



along the veins, which become brownish and dead. 

 The blade itself may often become affected. If 

 the attack develops late in the season, it is on the 

 pods that it becomes most characteristic and 

 destructive. Here it forms large, dark brown 

 sunken spots in the tissue of the pods. The spores 

 of the fungus may often be seen as a tiny pink 

 mass at the center of these spots or pits. The dis- 

 ease gradually works through the pods, and, at- 

 tacking the seeds, forms pits or discolored places 

 in them. When the seeds are dried the fungus 

 becomes dormant, only to become active again the 

 next season, when the diseased cotyledons are lifted 

 above the soil on the growing stalks. Diseased seed 

 usually may be recognized by the discolored areas 

 on the coat and by the shriveled condition. 



Weather conditions do not cause or originate 

 bean anthracnose, but they have very much to 

 do with its development and destructiveness. The 

 spores are held together by a gummy substance 

 which is easily dissolved in water, permitting them 

 to be disseminated to healthy plants by means of 

 insects, tools of tillage and in other ways. It is for 

 this reason that tilling beans while wet with dew 

 or rain almost always results in marked increase 

 of anthracnose. 



The treatment for anthracnose must be pre- 

 ventive rather than curative. Below are given 

 what are now considered to be the best means 

 of controlling this trouble : 



(1) Plant clean seed. If possible, secure seed 

 from fields known to be free from the anthracnose. 

 If seed from diseased fields must be planted, it 

 should be hand-sorted carefully, and all seeds not 

 perfect and bright should be rejected. 



(2) Go over the field just after the beans are up, 

 and carefully remove and burn all diseased seed- 

 lings. If left on the ground they will serve as 

 centers of infection for the growing plants. 



quarts water ; boil until a clear brown solution is 

 secured). Add this to one barrel of the Bordeaux. 

 Apply thoroughly with a nozzle giving a fine 

 spray. The first application should be made just 

 about the time the third leaf is expanding, or 



Bean plant in crop. 



(3) Spray thoroughly with Bordeaux mixture. 

 The normal strength should be used : 6 lbs. vitriol, 

 4 pounds lime, 50 to 60 gallons water. The addition 

 of resin soap wilt add to the effectiveness of the 

 mixture by making it spread more evenly, and 

 it will be less easily washed off by rains (resin 

 soap : 2 pounds resin, 1 pound crystallized salsoda, 2 



fis?!-'*.^ 



v."-i'-i^ " -^ .... 



Fig. 302. Bean liarvester. 



earlier if the disease appears to any considerable 

 extent. Repeat the application three or four times 

 at intervals of ten to fourteen days or whenever 

 the rains wash the Bordeaux off. 



(4) Do not hoe or cultivate diseased beans when 

 they are wet, as this will tend to spread the dis- 

 ease to healthy plants. 



Insed enemies. 



The most troublesome insect pest of the bean 

 industry in localities where it abounds is the bean- 

 weevil {Bruchus obteetus). The adult is a brown- 

 gray beetle about an eighth of an inch in length. 

 In the field, the eggs are deposited on or inserted 

 in the pod through a hole made by the jaws of the 

 female and through openings caused by the drying 

 and splitting of the pods. In dried beans the eggs 

 are dropped loosely among the beans or placed in 

 the holes made by the beetles in their exit from 

 the seed. The eggs hatch in five to twenty days, 

 being much influenced by temperature. The young 

 larvsB burrow into the beans and there undergo 

 their transformations, emerging as mature beetles. 

 The larval stage lasts eleven to forty-two days, 

 and the pupal stage five to eighteen days, so that 

 the life-cycle covers a period twenty-one to eighty 

 days according to season and locality. Hence a 

 number of generations are produced annually. In 

 localities where these beetles abound the damage 

 done to the mature beans is often such as to render 

 them valueless for human food or for seed and of 

 Ifut little value for stock-feeding. 



No effective means are known for the prevention 

 of the attacks of the bean-weevil in the field ; 

 hence, we must place our chief reliance on the 

 thorough destruction of the insects in the dried 

 seed and perhaps not attempt the production of 

 culinary dried beans in localities infested with the 

 weevil. Fortunately the weevil seems not to have 

 established itself in those parts of the United 

 States where the dried-bean industry is most 

 developed, which is the region bordering on the 

 Saint Lawrence river and the Great Lakes. The 

 northern counties of New York seem to be free 



