( ( When ( ( ( a ( plant 's ) ) ( vascular tissue ) ) ( develops ( in ( discrete bundles ) ) ) ) ) ( , ( it ( ( is ( said ( to ( have ( a eustele ) ) ) ) ) . ) ) ) )
(ROOT (S (SBAR (WHADVP (WRB When)) (S (NP (NP (DT a) (NN plant) (POS 's)) (NN vascular) (NN tissue)) (VP (VBZ develops) (PP (IN in) (NP (JJ discrete) (NNS bundles)))))) (, ,) (NP (PRP it)) (VP (VBZ is) (VP (VBN said) (S (VP (TO to) (VP (VB have) (NP (DT a) (NN eustele))))))) (. .)))
When a plant's vascular tissue develops in discrete bundles, it is said to have a eustele.
(ROOT (S (NP (NP (JJ Present-day) (NNS plants)) (SBAR (WHNP (WDT that)) (S (VP (VBP have) (NP (DT a) (JJ complex) (NN vascular) (NN tissue) (NN system)))))) (VP (VBP are) (VP (VBN called) (NP (NN vasuluar) (NNS plants)))) (. .)))