( ( This species ) ( ( is ( ( a ( serious threat ) ) ( to ( the ( Hawaiian flora ) ) ) ) ) . ) )
(ROOT (S (NP (DT This) (NNS species)) (VP (VBZ is) (NP (NP (DT a) (JJ serious) (NN threat)) (PP (TO to) (NP (DT the) (JJ Hawaiian) (NNS flora))))) (. .)))
This species is a serious threat to the Hawaiian flora.
(ROOT (S (NP (NNP Overharvesting)) (VP (VBZ is) (NP (DT a) (JJ serious) (NN threat)) (ADVP (RB particularly)) (PP (TO to) (NP (JJ aquatic) (NNS species)))) (. .)))