( ( ( ( ( Understory plants ) ( have disappeared ) ) and ) ( ( koa trees ) ( are dying ) ) ) . )
(ROOT (S (S (NP (JJ Understory) (NNS plants)) (VP (VBP have) (VP (VBN disappeared)))) (CC and) (S (NP (NN koa) (NNS trees)) (VP (VBP are) (ADJP (VBG dying)))) (. .)))
Understory plants have disappeared and koa trees are dying.
(ROOT (S (NP (NP (DT The) (NN understory)) (PP (IN of) (NP (DT the) (NN rainforest)))) (ADVP (RB commonly)) (VP (VBZ has) (NP (NP (NNS ferns)) (CC and) (NP (JJ other) (NN ground) (NNS plants)))) (. .)))