<http://webisa.webdatacommons.org/404657697>	<http://www.w3.org/ns/prov#wasQuotedFrom>	<purdue.edu> .
<http://webisa.webdatacommons.org/prov/372107134>	<http://www.w3.org/ns/prov#wasDerivedFrom>	<http://webisa.webdatacommons.org/404657697> .
<http://webisa.webdatacommons.org/404657697>	<http://www.w3.org/1999/02/22-rdf-syntax-ns#type>	<http://www.w3.org/ns/prov#Entity> .
<http://webisa.webdatacommons.org/404657697>	<http://www.w3.org/ns/prov#value>	"Organic matter may be added by returning the spent vines to the field, applying manure or plowing under a winter cover crop such as vetch or small grain." .