Refactor the unstructured text into a valid JSON dictionary. The key names follow the Darwin Core Archive Standard. If a key lacks content, then insert an empty string. Fill in the following JSON structure as required: {"catalogNumber": "", "order": "", "family": "", "scientificName": "", "scientificNameAuthorship": "", "genus": "", "subgenus": "", "specificEpithet": "", "verbatimTaxonRank": "", "infraspecificEpithet": "", "identifiedBy": "", "recordedBy": "", "recordNumber": "", "verbatimEventDate": "", "habitat": "", "occurrenceRemarks": "", "associatedTaxa": "", "country": "", "stateProvince": "", "county": "", "municipality": "", "locality": "", "decimalLatitude": "", "decimalLongitude": "", "verbatimCoordinates": "", "minimumElevationInMeters": "", "maximumElevationInMeters": ""}
DIOSCOREA VILLOSA ^  growing overshrubs at edge of swamp. s   united states IwZ   Sf_  elizabeth halfert           C dioscorea   D8b6 MICHIGAN   _Wr CASS   s.n. N2     :G:  1 339994   `P silver creek twp.
{"catalogNumber": "1339994", "order": "", "family": "", "scientificName": "Dioscorea villosa", "scientificNameAuthorship": "", "genus": "Dioscorea", "subgenus": "", "specificEpithet": "", "verbatimTaxonRank": "", "infraspecificEpithet": "", "identifiedBy": "", "recordedBy": "Elizabeth Halfert", "recordNumber": "s.n.", "verbatimEventDate": "", "habitat": "Growing over shrubs at edge of swamp.", "occurrenceRemarks": "", "associatedTaxa": "", "country": "United States", "stateProvince": "Michigan", "county": "Cass", "municipality": "", "locality": "Silver Creek Twp.", "decimalLatitude": "", "decimalLongitude": "", "verbatimCoordinates": "", "minimumElevationInMeters": "", "maximumElevationInMeters": ""}