( ( Pollen ( of ( wind-pollinated ( flowering plants ) ) ) ) ( ( ( ( tends ( to ( be ( ( small and ) weightless ) ) ) ) , ) ( produced ( in ( ( dull-colored flowers ) ( which ( sometimes ( lack ( nonessential parts ) ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (NP (NNP Pollen)) (PP (IN of) (NP (JJ wind-pollinated) (NN flowering) (NNS plants)))) (VP (VBZ tends) (S (VP (TO to) (VP (VB be) (ADJP (JJ small) (CC and) (JJ weightless))))) (, ,) (S (VP (VBN produced) (PP (IN in) (NP (NP (JJ dull-colored) (NNS flowers)) (SBAR (WHNP (WDT which)) (S (ADVP (RB sometimes)) (VP (VBP lack) (NP (JJ nonessential) (NNS parts)))))))))) (. .)))
Pollen of wind-pollinated flowering plants tends to be small and weightless, produced in dull-colored flowers which sometimes lack nonessential parts.
(ROOT (S (NP (NP (NNS Flowers)) (VP (VBN pollinated) (PP (IN by) (NP (NN wind))))) (ADVP (RB generally)) (VP (VBP lack) (NP (JJ brightly) (VBN colored) (NNS parts))) (. .)))