( Invasive ( Exotic ( Species . ) ) )
(ROOT (NP (NNP Invasive) (NNP Exotic) (NNP Species) (. .)))
Invasive Exotic Species.
(ROOT (S (NP (JJ Exotic) (NNS species)) (VP (VBP are) (ADVP (RB also)) (VP (VBN called) (NP (JJ invasive) (NNS species)) (SBAR (IN because) (S (NP (PRP they)) (VP (VBP threaten) (NP (JJ other) (NNS species))))))) (. .)))