MEXICAN BEAN BEETLE IN THE SOUTHEAST. 29 



GENERAL METHODS OF CONTROL. 



Reduction of the infestation by cleaning up hibernation quarters 

 offers an excellent method of control. In sections where waste 

 lands are sought by the beetle, cleaning up can best be accomplished 

 during the fall or spring by burning. Fence rows and inaccessible 

 portions can be burned effectively by means of a blowtorch designed 

 ior the purpose, along the lines of a cactus or pear burner, such as is 

 used in the Southwest for burning spines from prickly pear. It has 

 been discovered that the beetle seeks places somewhat sheltered and 

 where accumulations of leaves, pine needles, or plant debris occur. 

 In such instances the material may be gathered in piles and burned, 

 with especial care to prevent the spread of the fire over woodlands. 



Burning can not usually be recommended for the Southeast be- 

 cause of the loss which would result in many sections where wood- 

 lands are abundant and are of economic value. Loss of timber, 

 game, and beneficial insects in many cases would exceed the benefit 

 gained, since the value of the bean crop would not equal the loss. 

 Also, the beetle is capable of long flights to hibernation, and the area 

 to be burned would be greater than with many other species of in- 

 sects. In more densely populated sections, or in sections where the 

 major part of the land is tilled, and where waste places are necessar- 

 ily sought by the beetle, this practice will undoubtedly be very bene- 

 ficial. Where woodlands are relatively small, burning of the ma- 

 terials which shelter the beetles may be practiced without detriment 

 to the timber. This practice would require a close community effort 

 over a considerable area, and would be promising only in cases 

 where the area suitable for hibernation is restricted. 



Under conditions of severe infestation, fields which are badly in- 

 jured should be plowed under before the larvse develop into beetles. 



Covering any stage of the beetle with 1 inch or more of clay soil 

 during hot weather destroys it. 



The growing of beans under conditions of heavy infestation is im- 

 possible without the use of remedial measures. Only as many beans 

 as can be treated should be planted. The expense of treating pole 

 beans, on account of the difficulty of application and the longer 

 period to maturity, which involves more applications, makes it ad- 

 visable to grow only bush beans where infestation is heavy. 



Where green beans are grown, the infested fields should be plowed 

 as soon as the crop is picked. This will destroy large numbers of all 

 stages of the bean beetle and will reduce the infestation. Community 

 effort is essential in this practice, and will benefit each grower. 



For the winter months fields should be planted to cover crops 

 best suited to conditions. 8 This will add organic matter to the soil 

 and stimulate a vigorous growth and early maturity the following 

 year, thus tending to compensate for bean beetle injury. 



Plant varieties which do not produce large, bushy foliage. Too 

 leafy a foliage can not be as thoroughly covered by arsenicals as 

 varieties which produce less foliage. 



Plant seed in the drill. Clumps of plants are more difficult to 

 reach with insecticides than row crops. 



8 Farmers' Bulletin 1250, entitled "Green Manuring." 



