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": ""}
POLK <r   $5k (Michx.) Nees ex Steud.   @ R 1966-06I-28 United States 6+   ` ERAGROSTIS PECTINACEA       NL x@T Poaceae    d Eragqrostis   &4. poales     <L)s 668     hR 1413597  pectinacea U   
{"catalogNumber": "1413597", "order": "Poales", "family": "Poaceae", "scientificName": "Eragrostis pectinacea", "scientificNameAuthorship": "(Michx.) Nees ex Steud.", "genus": "Eragrostis", "subgenus": "", "specificEpithet": "pectinacea", "verbatimTaxonRank": "", "infraspecificEpithet": "", "identifiedBy": "", "recordedBy": "", "recordNumber": "668", "verbatimEventDate": "1966-06-28", "habitat": "", "occurrenceRemarks": "", "associatedTaxa": "", "country": "United States", "stateProvince": "", "county": "Polk", "municipality": "", "locality": "", "decimalLatitude": "", "decimalLongitude": "", "verbatimCoordinates": "", "minimumElevationInMeters": "", "maximumElevationInMeters": ""}