Using a facet query like facet.query=+water +treatement +plant
... should give a count of 0 to documents not having all tree terms. This could do the trick, if I understand how this parameter works.
Using a facet query like facet.query=+water +treatement +plant
... should give a count of 0 to documents not having all tree terms. This could do the trick, if I understand how this parameter works.