TORREYA 



Vol. 22 No. 5 



September-October, 1922 



AUSTRIAN FIELD CRESS: A xNEW WEED IN THE 

 UNITED STATES. 



Albert A. Hansen 



During June 192 1, the attention of the writer was attracted 

 to a weed that is over-running certain sections of Borderland 

 Farm, New Milford, Orange County, New York. The plant 

 grew in dense masses to the exclusion of practically all other 

 vegetation. 



At that time, the plant was in full bloom, and the tiny flowers 

 gave the entire infested area a yellow cast. One field, which 

 was used as a pasture, contained about five acres of infestation; 

 patches of the weed occured at a distance of from two to three 

 hundred yards from the main area of infestation, while the 

 roadsides on the farm were thoroughly infested. 



Since the plant was new to the writer, specimens were secured 

 and identified. Indentification being impossible with American 

 manuals, European works were consulted and the plant was 

 identified as Roripa austriaca, Spach. {Nasturtium austriacum 

 Crantz) . 



The identification was verified by the office of Economic 

 and Systematic Botany of the United States Department of 

 Agriculture. The common name of the plant is field cress or 

 Austrian field cress. A picture of the field cress is contained 

 in Reichenbach 's "Icones Flora Germanica," figure 4295. 



The following description of the species was translated from 

 Boissier's Flora Orientales ll:i8o by Mr. S. F. Blake. 



"Glabrous perennial; leaves oblong-spatulate , the lower 

 petioled, entire or toothed, the others sessile, auriculate-cordate, 

 denticulate; pods globose, much shorter than the erect-spreading 

 pedicel; the valves nerveless; seeds scabrous under a lens." 

 No entire-leaved specimens were found among the plants 

 growing in New York. 



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