danes-blood

from The Collaborative International Dictionary of English v.0.48

Danewort \Dane"wort`\, n. (Bot.)
   A fetid European species of elder ({Sambucus Ebulus}); dwarf
   elder; wallwort; elderwort; -- called also {Daneweed},
   {Dane's weed}, and {Dane's-blood}.

   Note: [Said to grow on spots where battles were fought
         against the Danes.]
         [1913 Webster]