WEED MIGRATION 



697 



mmm^^^-^ 



Fig. 537. Caster Oil plant. Cultivated as an ornamental plant in Iowa, but u 



troublesome weed in South Africa. 



(After Faguet.) 



temulentum) , plantain {Plantago major), ribgrass {Plantoffo 

 lanceolata), sheep sorrel {Bumex acetosella), curled dock (Bumex 

 crispus), black nightsbade (Solanum nigrum), dandelion {Taraxa- 

 cwm offiemale), cow-herb (Saponmia vaccaria), vetch {Vicia sch 

 tiva). III. Common; spiny amaranth {Amaranthus spinosus), 

 goosefoot {Chenopodium album), hemp (Cannabis indica), nut 

 grass (Oypertis esculentus), shoo-fly {Hibiscus trionum), lady's 

 sorrel (Oxalis cormc"ulatd) , purslane {Portulaca oleracea), castor- 

 oil bean (Biciwus communis), and caltrop {Tribulus terrestris). 

 IV. Abundant; (the most common species) purple amaranth 

 (AwMranthus paniculatus) , sticktight (Bidens pilosa), jimson weed 

 (Datura stramonium), purple thorn apple (Datura tatula), wire 



