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such as work their injury below the surface of the ground. The larvae 
of Elaters devastate our lowlands and the grubs of Lachnosterna ravage 
the higher lands, while Cutworms, Web Worms, and Corn Root- worms 
are found generally diffused over both. The Corn-Root- worra, Diabrotica 
lo unicornis, excepted, all of these seem more destructive to a crop of 
grain following a grass crop or pasture. Yet this is not always true. 
I have known of fields of corn being seriously affected by white grubs 
when such fields had not been devoted to grass for a single season in 
twenty years. 
In the case of Wire Worms some good results may be secured by fall 
plowing, though as the adults emerge in August or September and 
winter over, also in this stage, we can hope to do little with these. 
There are, however, during the winter two younger generations in the 
soil, and against these a fall plowing may and evidently does have an 
ill effect. What a summer fallow would do I have had no opportunity 
of learning. There are no end of reported successes and failures among 
farmers, but there is so much obscurity shrouding these that one can 
not judge of their authenticity. Once, and once only, have I felt quite 
sure of having beaten these pests. This was in the case of a field of 
grass land, plowed in spring and planted with potatoes. The worms 
nearly ruined the crop, and in the fall the ground was still well popu- 
lated with them. The following spring, potatoes' that had escaped 
notice when the crop was harvested seemed to attract the worms, and 
the latter were found burrowing in the tubers in great numbers. On 
my suggestion, hogs were turned into the field, and these rooted out 
and promptly disposed of both potatoes and worms, no injury occurring 
to the following crop, which, was of corn. There may be some virtue 
in the application of kaiuit, although this has not as yet been thor- 
oughly and clearly demonstrated, and, besides, over the vast corn belt 
of the Northwest, its application is impracticable. For myself, I am 
willing to confess ignorance of any unfailing, practical measure, either 
of prevention or destruction. Fall plowing and a rapid rotation of 
crops are as yet the best measures we can recommend. 
White Grubs, the larvse of several of our species of Lachnosterna, 
appear to give preference to the higher lands. Where the soil of such 
lands is of such a nature as to wash easily during winter and spring, 
fall plowing results in the washing out of great gullies, thus consti- 
tuting a grave objection to the measure. Outbreaks of this pest seem 
to be usually of triennial occurrence, different localities being affected 
during different years, and I have thought we might accomplish some- 
thing by mapping out these areas, and so warn the agriculturist of 
their probable appearance. Here, however, the same trouble awaits us. 
A single mistaken prediction discourages the few who will follow our 
direction, and we get only derision from the remainder. In my own 
correspondence I have advocated the same measures against these as 
in case of the Wire Worms, viz, a rapid rotation of crops, especially of 
