Qualifier
collection_date
Definition date that the specimen was collected
Value Format
"DD-Mmm-YYYY", "Mmm-YYYY" or "YYYY" 
Example /collection_date="21-Oct-1952" /collection_date="Oct-1952"
/collection_date="1952"
Comment full date format DD-Mmm-YYYY is preferred; where day and/or month of collection is not known either "Mmm-YYYY" or "YYYY" can be used; three-letter month abbreviation can be one of the following: Jan, Feb, Mar, Apr, May, Jun, Jul, Aug, Sep, Oct, Nov, Dec.