332 



FARMERS' REGISTER— WEEVIL IN WHEAT. 



facts tending to enable the farmer to prevent its 

 ravages must be acceptable. Believing that the 

 facts noled, and the observations made by myself 

 several years past, may have that tendency, or 

 lead others to make observations that will, 1 am 

 induced to transcribe the notes and observations J 

 then made, and forward for the American Farmer. 



As early as convenient after harvest in 1825, I 

 got out some wheat for present use, and put it 

 away on a plank floor in an upper room over the 

 kitchen. During August, I heard much com- 

 plaint among my neighbors of the ravages of the 

 weevil in their wheat, and was induced to examine 

 my own. I found that which had been cleaned out 

 much Aveevil eaten, while that in the chaff, eitlier 

 in the barn or stack, was much less affected. I 

 recollected that soine, though very few, were to be 

 seen when the wheat Avas got out. The extraordi- 

 nary, and so greatly disproportionate increase of 

 the fly in the cleaned wheat, set my mind at work 

 to find out, if possible, the cause of that difference. 



I had heard of tv/o theories on the subject — the 

 first, that there was a living principle in all wheat, 

 which in a particular state of heat and moisture, 

 would become animated and produce the weevil. 

 The second, and more common one was, that there 

 was some parent fly which resorted to the field, 

 and impregnated the grain during its soft slate, in 

 the manner that a fly is known to do in the garden 

 pea. The situation of the cleaned wheat, over a 

 room in which there was always more or less fire, 

 was in some degree favorable to each of these theo- 

 ries — yet on reflection I doubted the truth of either. 

 I argued thus. If there is a principle or quality 

 in the grain, which a given slate of atmosphere 

 could animate, so as to produce an insect, the effect 

 would be so general, and so extensive, in the cli- 

 mate where it operates, as to destroy at once, 

 whole crops of grain — whereas it was well known, 

 that when the weevil is first discovered, its ravages 

 may be arrested in various ways. And moreover, 

 if this theory had been correct, it must long since 

 have been detected by the investigations of science. 

 As to the impregnation by a parent fly, I consider- 

 ed — that the period during which the operation 

 should take place, must of necessity be short, say 

 from five to ten days, immediately preceding the 

 ripening of the grain. When Ave reflect on the 

 immense number of grains destroyed in a bad 

 Aveevil year, it is obvious that if the number of 

 flies requisite to impregnate all these grains, in a 

 few days, should resort to the Avheat field, the num- 

 ber must be so exceedingly great, as often to have 

 attracted the attention of the vigilant and intelli- 

 gent agriculturist; such, no doubt, Avould often 

 have seen the parent fly in actual contact Avith the 

 grain in the ear, as in case of the pea. Again — if 

 all the grains become impregnated within a few 

 days of the same time, it should seem probable at 

 least, that the coming forth of tiie Aveevil would be 

 equally simultaneous — Avhereas it is equally Avell 

 known, that after the weevil fly begins to appear, 

 it progresses Avith increased ratio, till checked by 

 the cold of autumn. 



Distrusting tliese theories, and seeing the great 

 increase on Avheat tOAvhich the fly had free access, 

 I Avas led to the supposition that there must be a 

 continual increase, by propagation, during the 

 warm season. This suggested the idea of borrow- 

 ing a magnifying glass of a silversmith, for the 

 purpose of a more minute examination than I Avas 



capable of making with my spectacles, Avhich age 

 had obliged me to use. 



On the 22(1 of A\igust, by the use of the glass, I 

 discovered what I had never heard of before, the 

 eggs, or nits, of the grey weevil fly on many 

 grains of wheat. They Avere generally of a pale 

 reddish color, somewhat brighter than the color of 

 the Avheat, though some of them Avere nearly 

 Avhite. These eggs were mostly deposited in the 

 crease or indenture on one side of the grain, and 

 adiiered Avith a slight degree of tenacity. A num- 

 ber of these grains Avith eggs or nits on them, 

 Avere selected and put away in a saucer. They 

 were examined each day, but no perceivable 

 change until the 27th, Avhen instead of the trans- 

 parency Avhich they had exhibited, they appeared 

 to consist only of a coat or Aveb of the thinnest 

 conceivable texture. On pressing them they did 

 not crack as before. On closer examination a 

 number of small worms Avere seen, remarkably 

 active, some on the grains of Avheat, and some on 

 the saucer. On the 29th there Avas scarce a nit to 

 be seen in its original transparent state, so that all 

 the eggs or nits on the grains Avhich had been put 

 in the saucer, had been hatched in about three 

 days. I entertained no doubt that the little worm 

 had proceeded from the eo;^. And from the fre- 

 quent attempts Avhich it appeared to make to pene- 

 trate the grain, by its assiduous exertions at one 

 spot, I Avas led to the opinion that it did actually 

 eat its Avay tlu'ough the bran info the grain. 



I Avas then desirous to ascertain Avhether the 

 eggs or nits I had seen, Avere really those of the 

 weevil fly. To this end, I confined three of those 

 flies in a glass tumbler, by covering it with a book, 

 and put several grains of Avheat in with them. I 

 continued to notice them daily, till about the sixth 

 day, Avhen I found that tAvo of the flies Avere gone, 

 having been let out as I supposed by the children, 

 and one was dead. On examination, I found three 

 different bunches of nits on the bottom of the glass, 

 precisely like those I had seen on the Avheat. By 

 the help of the magnifying glass 1 could count 

 them, there Avere upwards of twenty eggs in each 

 bunch, the eggs in each several bunch adhering 

 together. This experiment I again repeated, Avith 

 the same result, except that the number of eggs 

 Avcre fewer. 



Du in g my attention to this subject, I became 

 enabled to pick out, almost unerringly, the grains 

 of wheat that had worms, however small. I found 

 them from the smallest size, scarcely larger than 

 those I had seen in the saucer, up to the size of the 

 maggot just before going into the chrysalis state. 

 I also could discern the hole, through Avhich ac- 

 cording to the opinion of some, the parent fly had 

 deposited the young in the grain, or through which, 

 as Avas my OAvn opinion, the Avorm itself had enter- 

 ed. This hole Avas not larger than Avould admit 

 the point of a very small needle — too small for the 

 naked eye of most persons. The grains impreg- 

 nated, I found vastly more numerous among the 

 cleaned Avheat, than among the unthrashed. 



On the unthrashed Avheat I found the nits on the 

 heads, generally on the inside of the outer coat of 

 the chaff, sometimes on the outside, rarely on the 

 grain. It Avas discovered at the same time that 

 the weevil Avas flying about the Indian corn in the 

 crib. I found on examination much of the corn 

 perforated, as the grains of wheat are, Avhen the 

 weevils has left them. It was easy also to distin- 



