THE CHINCH BUG IN IOWA. o 



a very short time immense numbers were struggling to escape from 

 the furrows and taking advantage of every object that would furnish 

 them a foothold upon which to pass. Many of them would accumu- 

 late at the side of the furrow next the grass, not even entering the 

 furrow. Subsequently many were found dead along the furrows, 

 some within, and others simply at the edge next the grass. Knowing 

 that the cast off skins of the larvae closely resemble dead bugs, I 

 examined a number of handfuls in order to be sure that they were 

 dead bugs and not merely the cast off skins of those that had 

 moulted. Whether they died from starvation or because they could 

 not secure the protection which they endeavor to obtain at night, I 

 do not pretend to say, though the former seems the more likely, since 

 many secreted themselves under weeds, straw and even in the earth, 

 to which all had access. Some bugs collected along the furrows 

 were destroyed by drawing heavy straw torches along over the 

 thickest masses. As the corn in this case was pretty well grown, the 

 farm management preferred to cut and shock it for fodder rather 

 than keep the furrows in order, and in a short time they ceased to be 

 any obstruction. The main difficulty with furrows as usually made, 

 is that they present at many points solid walls, pieces of sod, large 

 clods, tufts of grass, etc., which serve as highways for the migrating 

 host. I believe that the most effectual check will be made by draw- 

 ing a triangular block or weighted trough along a dry furrow or 

 between rows of corn simply over the surface of the loose earth. 

 The trough could be made by nailing together two pieces of plank 

 four to six feet long, fastening a hook at one end to hitch a chain to, 

 and weighting by putting in stones to which may be added the 

 weight of the driver. When used between corn rows to prevent 

 advance of bugs already in the field, it could be kept in position by 

 side pieces, which could also be arranged to make shallow marks, thus 

 forming three parallel furrows at once. To prevent the bugs passing 

 from wheat stubble to corn, furrows should be plowed some days 

 before migration begins, and the ground turned two or three times or 

 till well pulverized, then, as soon as bugs show any signs of travel- 

 ing, the trough should be drawn along the furrow to reduce the sides 

 to dust, and this process should be repeated every dry and hot day, 

 by ten o'clock in the forenoon, so long as bugs attempt to pass. The 

 bugs accumulated in the furrow will thus many of them be crushed 

 and the sides of the furrow kept finely pulverized. 



Experiments were also made with Pyrethrum and Bisulphide of 

 Carbon, the former proving entirely unsatisfactory, while the latter, 

 though promising to be of some value under certain conditions, will 

 need to be given further trial before a definite opinion as to its value 

 can be formed. 



While it is very desirable to find some cheap and efficient 

 method of destroying the bugs when present and destroying any 

 particular crop, the greatest reliance will probably always have to be 

 placed upon preventive measures, and the success of these will 

 depend upon the promptitude and energy with which they are 

 adopted by the farmers of every community in the State where bugs 

 are now present. 



The best known methods are summarized below. 



