Spanish needles vs shepherd's needle

Spanish needles

noun

  • A flowering plant, taxonomic name Bidens alba. 

shepherd's needle

noun

  • Beggarticks (Bidens spp.) 

  • Venus' comb (Scandix pecten-veneris) 

How often have the words Spanish needles and shepherd's needle occurred in a corpus of books? (source: Google Ngram Viewer )