2293 
the corn plant until the ear is fully matured—in fact, generally not until 
the stalk is quite dry. Up to the present time this borer has been found 
in the fall in the stems of the following plants: 
Sintattyweeder wea: eyeseeerd Polygonum hydropiper L. 
IREVEN ee droed Bae Haale d oy cheione Ambrosia artemisifolia L. 
AGENT EOC Waco ke poor A. trifida L. 
Indian mallow............. Abutilon theophrasti Medic. 
imson-weeden ates tas ss. Datura stramonium L. 
Goldennadir ees ate m cise» 4. Solidago sp.? 
[eat S-QUALCELS ae). sisal. > «s Chenopodium album L. 
Barnyardverass; 60...) 3. Echinochloa crus-galli Beauv. 
WOxtailietass carne se ss Setaria glauca Beauv. 
Cocklebunie veeciserae. esl Xanthium spinosum L. 
Western tickseed sunflower. Bidens aristosa Britton 
Common sunflower........- Helianthus annuus L. 
Rough pigweed............ Amaranthus retroflexus L. 
Mumbleweed\yvre san ste A. graecizans L. 
Prostrate pigweed.......... A. blitoides Wats. 
Spanishimeedles. 2. .n.s--- Bidens sp.? 
Waldvlettuce jaja .e eos ot Lactuca canadensis L. ~ 
Evening primrose.......... Oenothera hiennis L. 
Field corn. 
Sweet corn. 
This borer has not been found in any of 
the above weeds except where they were grow- 
ing near infested smartweed, and apparently it 
goes to them in fall as a more desirable place to 
hibernate than the smartweed stems. “It has 
not been, found in the stems of any weeds where ~ 
such stems were hard and woody, although it 
may be abundant in the softer parts of the same 
plants. In some fields where the smartweed 
was very heavily infested, the borers were found 
fully as numerous in the stems of some other 
weeds, as is shown by the following comparative 
counts made in plants other than smartweed: 
GO eters cae portale eee stenh es ayes! = 20 
Amaranthus retroflexus ......... 108 
WWamipisaq Watters’) yica- oat. 2 ayecera es 19 
RRaIoNW CCG a rarsieta create nel nensiitrene sats 23 
Sissi Hell a poh eee teenies Cer 99 
Barnyardreass ners avr ae sia efcic ce2 2 
So far as can be learned from the observa- Fic. 5a 
tions this season, no real injury has been done by Larvae of the 
Smartweed | European 
this native borer. Although as many as twenty borer corn-borer 
