In trying to correct a migration mistake where I forgot to set the entity Taxa in datset  to unlimited terms(default was 1) I ran into a problem with feeds.  Earlier I had used feeds to import the reversion numbers for the datasets since migrating did not bring over the revision numbers. It turns out the once a feed uses a variable as a unique id (in my case Data Set ID) only that feed importer will work.  Cloning it or setting up another will result in creating new nodes. So I had to patch feeds with feeds-guid-nonunique-per-feed-1539224-69.patch from this web page https://www.drupal.org/node/1539224 I first found useful information here - https://www.drupal.org/node/1789670 Note for this patch you need the latest feeds 7.x-2.0-beta1 After the patch I was able to successfully updated my Taxa variable to have multiple terms.  See https://www.isovera.com/blog/using-feeds-module-bulk-import-drupal-7 for details Update: 4Feb16  Using newer 78 patch.  One does need to uncheck the Unique box and ignored the hash so nodes are updated no matter what.  On the csv file with the update I replaced the ", " with a ; Tamper will just see the comma and leaves the space. I used ONLY a ;  no spaces bewteen the terms.  Jim

Update:  6Apr2017

In order to feed into taxa which is added to data set as a entity term I had to modify the feed importer as below. I probably can now delete field_data_set_species and just use filed_dataset_taxa.  With taxa as an entity term I can now export in the eml view

And tamper as:

An example csv file:

Dataset ID,Species
10026,"Carex bigelowii;Eriophorum vaginatum;Calamagrostis lapponica;Betula nana;Salix pulchra;Salix phlebophylla;Vaccinium uliginosum;Vaccinium vitis-idaea;Arctostaphylous alpina;Cassiope tetragona;Ledum palustre;Andromeda polifolia;Empetrum nigrum;Rubus chamaemorus;Polygonum bistorta;Petasites frigida;Pedicularis;Sphagnum"