5() 



or tlu> cluh-nisli or oIIkm- tliick-s((Mnn\0(l grasses with l)ull)oiis rt)ols are 

 eonimoii in tlu> turf, the corn is extremely likely to be badly injured if 

 not wholly destroyinl by one of the swamp-lovinii; species of this group. 

 If such land is poorly cultivated, allowing tliese bulb-root grasses to grow 

 up again, the injury may continue for at least another year. If an old 

 tiniothy-scnl. either pur(^ or niixeil with some other grass, is plowed in 

 spring and planted immediately to coi-n, this crop is likely to be severely 

 injured b>- other and smaller species than those which attack the crop 

 in swamps. I have known but one case of any considerable injury by 

 these insects to a field of corn in Illinois except under one of the above 

 conditions. 



The damage on swamp sod is frequent'y so serious and extensive as 

 to require the repeated re[)laiiting of large fiekls of corn. On timothy 

 sod it is not often so complete, a badly infested field rarely having as 

 nuich as lifty per cent, of the plants injured, and these less seriously be- 

 cause the bill-bugs breeiling in timothy average much smaller than those 

 living in swampy situations. 



Injuries to Grass and Grain. — The injury to timothy meadows by the 

 work of both beetles and larva^ is sometimes considerable, the former 

 killing the stalk, and the latter destroying an entire stool by hollowing 

 out the bulbous root. 



In West \'irginia, according to Hojikins, injuries by one of these 

 beetles (scidplilis) are among {\\c prime causes of the early decay of 

 timothv meadows. One of the smaller sjiecies. parvulus (Fig. 27), has 

 also been reported as slightly injurious in the lar\-al state to wheat, oats, 

 and barlev. The grub feeds within the straw until it becomes too large 

 for its burrow, and it then passes to the roots, often killing an entire stool 

 of grass in this way. 



Distribuiion. — The known distrilnitiiMi of these beetles is very gen- 

 eral throughout the United States and Canada, and in Illinois they may 

 occur anywhere within our boundaries if local conditions permit them to 

 breed. 



Life Histor;/. — 80 far as known to me, all our bill-bugs pass the winter 

 in the beetle stage on the ground under rubbish or in other protected 

 situations, and all whose life history has biHMi closely observed, make 

 their apjiearance in s}u-ing usually in tieUls in which they have lived as 

 larva\ and where they ha\e fed on the roots of grasses or grass-like 

 plants the preceding year. As the adult beetles feed on the same plants 

 as their larva:>. there is little to tempt them to migrate fn)m one field to 

 another, and the known facts clearly indicate that they i>ass the winter, 

 as a rule, in the same fields in which they went through their earlier 

 stages, provided that these fieUls have been uuilisturbed. All who.se 

 life history has been traceil with sullicient fullness to warrant an opinion 

 are apparently single-brooded, although the long breeding jieriod and the 



