( ( Most abundant ) ( ( is ( ( ( the ( cholla ( or ( buckhorn cactus ) ) ) ) - ) ( ( thin ( green arms ) ) ( well ( protected ( by spines ) ) ) ) ) ) . ) )
(ROOT (SINV (ADJP (RBS Most) (JJ abundant)) (VP (VBZ is)) (NP (NP (DT the) (NN cholla) (CC or) (NN buckhorn) (NN cactus)) (: -) (NP (NP (JJ thin) (JJ green) (NNS arms)) (VP (ADVP (RB well)) (VBN protected) (PP (IN by) (NP (NNS spines)))))) (. .)))
Most abundant is the cholla or buckhorn cactus - thin green arms well protected by spines.
(ROOT (S (NP (NP (DT The) (NNS spines)) (PP (IN of) (NP (DT a) (NN cactus)))) (VP (VBP help) (SBAR (S (NP (PRP it)) (VP (VBP survive) (SBAR (IN because) (S (NP (NNS spines)) (VP (VB protect) (NP (DT the) (NN cactus)) (PP (IN from) (NP (NNS animals)))))))))) (. .)))