T h e u p t a k e of Fe b y roots a n d apical leaves of tile s u b m e r s e d a q u a t i c p l a n t Hydrilla verticillata Royle was s t u d i e d using 59FeEDTA. 59FeEDTA was a b s o r b e d b y b o t h roots a n d apical leaves, a n d t r a n s l o c a t e d to t h e other p a r t s of t h e plant. A p p r o x i m a t e l y 3 % of t h e t o t a l 59FeEDTA a b s o r b e d b y t h e roots over a period of 60 h was t r a n s l o c a t e d to t h e leaves. D o w n w a r d t r a n slocation of 59FeEDTA from t h e apical p o r t i o n of t h e p l a n t to t h e lower leaves was a p p r o x i m a t e l y 2 1 % of t h e a m o u n t absorbed.