gists to believe that, like many others of the Scolytiche, the insect does 

 not attack the plant until the latter has become weakened by age or is 

 diseased. But, in this country, at least, this can not be true, for tin- 

 reasons just given. It is not improbable, however, that, as between 

 tAvo plants with roots of the requisite size, an unhealthy one would be 

 preferred by the beetles rather than one in a thoroughly vigorous condi- 

 tion. But, as yet, there have been no observations tending to verify 

 this hypothesis. A diseased clover root, or one that has begun tit de- 

 cline from effects of age, is first affected at the heart; and, as will be 

 observed from figure 4, this is the part first attacked by the root-borer. 



EFFECT UPON THE PLANT. 



While an infested clover plant sooner or later succumbs to an attack 

 by this insect, life may be lengthened or shortened by meteorological 

 conditions. Thus, if the spring or early summer is very dry, the plants 

 begin to die in patches late in June, as soon as the hay crop is removed; 

 but if there is much rain during this period, the weakened plants ma}' 

 continue to live until winter, dying out before spring. In either case 

 the farmer is likely to be misled and to attribute the loss to the weather. 

 The summer of 1905 was not a dry one. Copious rains fell with suffi- 

 cient frequency to enable all but the most seriously affected plants to 

 survive. A prominent seedsman of Indiana, who was much among 

 clover fields, thus described the situation in October: 



In driving around this year and examining clover fields, we have found that 

 several fields which apparently should have produced an immense amount of 

 seed, or at least, say, 3 or 4 bushels to the acre, * * * did not shake out 

 anything. We pulled up some plants and discovered that the plant broke off at 

 the crown; or if any of the root did come with it, it was small and decayed. 

 On close investigation we discovered a little white worm which seemed to be in 

 abundance and working amongst the roots. We noticed this in a number of 

 fields and have been wondering what it was. We have also had samples of 

 clover plants from other sections of Indiana showing these conditions and 

 almost invariably the yield of such fields was less than a bushel per acre, ami in 

 many instances hulling was abandoned and the huller taken out of the field. 



NATURAL ENEMIES. 



While Dr. Riley found the larva of one of the common soldier beetles, 

 probably Telephones bilineatus, attacking the larva' of the borer, and 

 although it probably has other enemies, both among insects and birds, 

 these have so far proven of little economic importance. 



PREVENTIVE MEASURES. 



The only preventive measure yet tried that gives any promise of suc- 

 cess is summer fallowing as soon as the hay crop is removed. 



At this time the young are in an immature state and, if deprived of 

 food, must perish. They can not migrate from one clover root to 

 another, and, if the meadow is now broken up, throwing the roots up 



