WATERCRESS 



Radicula Nasturtium-aquaticum L. 



Watercress is a widespread perennial herb that is seen growing on 

 margins of small streams and shallow water areas. This particular 

 species is the common watercress that is collected from fresh springs 

 for salads. Because of the creeping and freely rooting stem growth 

 habit, watercress can extend into the shallow, slow-moving water of 

 irrigation canals and obstruct waterflows. This plant is a troublesome 

 weed in irrigation drainage channels when not kept in check. 



Watercress is quite easily recognized by its fleshy leaf structure that 

 is made up from three to nine oval-shaped leaflets that combine to 

 form a single compound leaf. The plant roots extensively from the 

 prostrate stems. Small flowers with petals are produced at the terminals 

 of the stems. The slim fruit pod, or silique, which is typical of plants 

 of the mustard family will be seen below the flower heads, the older 

 ones elongating as the seeds mature. 



This plant extends its growth from the shallow shore margins into 

 the water, often completely submersed for long periods. 



Species of watercress are widespread and can be expected to be 

 found on wet areas of all Western irrigation systems although usually 

 in localized infestations. 



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