( ( ( Poison ( Ivy 's ) ) ( distinctive ( leaf pattern ) ) ) ( ( is ( groups ( of ( ( three leaflets ) ( ( occurring alternately ) ( along ( the stem ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (NP (NNP Poison) (NNP Ivy) (POS 's)) (JJ distinctive) (NN leaf) (NN pattern)) (VP (VBZ is) (NP (NP (NNS groups)) (PP (IN of) (NP (NP (CD three) (NNS leaflets)) (VP (VBG occurring) (ADVP (RB alternately)) (PP (IN along) (NP (DT the) (NN stem)))))))) (. .)))
Poison Ivy's distinctive leaf pattern is groups of three leaflets occurring alternately along the stem.
(ROOT (S (NP (NN Poison) (NN ivy)) (ADVP (RB typically)) (VP (VBZ has) (NP (NP (CD three) (NNS groups)) (PP (IN of) (NP (NNS leaves))))) (. .)))