( ( not ( ( ( ( ( ( a threat ) to ) ( the forests ) ) , ) and ) they ) ) ( only ( ( affect ( ( a ( small percentage ) ) ( of trees ) ) ) . ) ) )
(ROOT (S (NP (RB not) (NP (DT a) (NN threat)) (TO to) (NP (DT the) (NNS forests)) (, ,) (CC and) (NP (PRP they))) (ADVP (RB only)) (VP (VB affect) (NP (NP (DT a) (JJ small) (NN percentage)) (PP (IN of) (NP (NNS trees))))) (. .)))
not a threat to the forests, and they only affect a small percentage of trees.
(ROOT (S (NP (NP (DT An) (NN acorn)) (VP (VBG growing) (PP (IN into) (NP (DT an) (JJ adult) (NN tree))))) (VP (MD will) (VP (VB take) (NP (DT the) (JJS longest) (NN time)) (S (VP (TO to) (VP (VB observe)))))) (. .)))