690 



WEED FLORA OF IOWA 









Wig. 532-A. Prostrate Pigweed [Amarantlms 'bUtoides.) 

 (Photographed by Hart.) 



multiflorus) , fragrant goldenrod {Solidago odora), and many others 

 occupy the ground. What becomes of the flora when the sod and 

 its flora have borne their own peculiar vegetation ? Comparatively 

 few of the original inhabitants thereof remain as a part of the flora. 

 The weeds most likely to appear here are such as have been partially 

 adjusted to the open conditions. In such places it was not un- 

 common in the early days to find that such weeds as the common 

 Iowa tumble weed {Anuiranthus graecizans) , tickle-grass {Pamcum 

 capillare), creeping verbena {Verbena iracteosa), milk spurge or 

 milk purslane ( Euphorbia maculata and E. geyeri), evening prim- 

 rose {Oenothera biennis), horSeweed {Erigeron canadensis), blue 

 vervain {Verbena stricta), persisted for a few years, perhaps with a 

 few other perennial weeds like flowering spurge {Euphorbia corol- 

 lata) , Helianthus occidentaiis and Desmodium canescens, especially 



