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MINNESOTA BOTANICAL STUDIES 



the Salix-Amorpha combination which has already been discussed 

 under woodland vegetation. The group is not to be considered as 

 playing a significant role in the lowland successions which culmin- 

 ate in the hay meadow association, but rather as an intruding type 

 which here and there takes a conspicuous part in the vegetative 

 cover of certain meadows. 



RUDERAL VEGETATION 



There are a number of plants that are regularly found in and 

 about waste places. To this number may be added others that are 

 regular members of certain of the above plant associations which 

 now and then reveal a decided ruderal tendency. The following 

 list includes the commoner plants of this nature. 



RUDERAL SPECIES 



Amaranthus graecisans 

 Amaranthus hybridus 

 Amaranthus retroiiexus 

 Amaranthus torreyi 

 Ambrosia artemisiaefolia 

 Argem,one intermedia 

 Bromus brizaeformis 

 Bromus tectorum 

 Cannabis sativa 

 Cassia chamaecrista 

 Chaetochloa glauca 

 Chaetochloa viridis 

 Chenopodium album 

 Chenopodium hybridum 

 Cleome serrulata 

 Cryptanthe fendleri 

 Cycloloma atriplicifolium 

 Dyssodia papposa 

 Echinochloa crus-galli 

 Eragrostis pectinacea 



Helianthus petiolaris 

 Hordeum jubatum 

 Hordeiim pusillum 

 Iva xanthifolia 

 Lactuca canadensis 

 Lactuca pulchella 

 Lepideum apetalum 

 Leptilon canadense 

 Ma Iva rotundifolia 

 Melilotus alba 

 Melilotus officinalis 

 Munroa squarrosa 

 Oxalis stricta 

 Physalis heterophylla 

 Polygonum aviculare 

 Polygonum convolvulus 

 Rum ex venosus 

 Salsola tragus 

 Solanum rostratum 

 Verbena stricta 



Glycyrrhisa lepidota 



The species of Amaranthus, Ambrosia, the Chaetochloas, Che- 

 nopodium album, Cycloloma, Hordeum jubatum, Helianthus petio- 

 laris, the Lactucas, Polygonums, Salsola, and Solanum rostratum 

 are frequent and abundant in old fields and gardens. These species 



