( ( ( ( ( ( ( The ( standard replacement ) ) ( for soil ) ) ( is ( peat moss ) ) ) , ) but ) ( there ( has ( ( been ( concern ( over ( the ( past ( few years ) ) ) ) ) ) ( that ( peat ( is ( a ( non-renewable resource ) ) ) ) ) ) ) ) ) . )
(ROOT (S (S (NP (NP (DT The) (JJ standard) (NN replacement)) (PP (IN for) (NP (NN soil)))) (VP (VBZ is) (NP (JJ peat) (NNS moss)))) (, ,) (CC but) (S (NP (EX there)) (VP (VBZ has) (VP (VBN been) (NP (NP (NN concern)) (PP (IN over) (NP (DT the) (JJ past) (JJ few) (NNS years)))) (SBAR (IN that) (S (NP (NN peat)) (VP (VBZ is) (NP (DT a) (JJ non-renewable) (NN resource)))))))) (. .)))
The standard replacement for soil is peat moss, but there has been concern over the past few years that peat is a non-renewable resource.
(ROOT (S (NP (NNP Soil)) (VP (VBZ is) (NP (NP (DT a) (JJ renewable) (NN resource)) (SBAR (WHNP (WDT that)) (S (VP (MD can) (VP (VB take) (NP (NP (CD thousand)) (PP (IN of) (NP (NNS years)))) (S (VP (TO to) (VP (VB form)))))))))) (. .)))