The Collaborative International Dictionary of English v.0.48:

Windlestrae \Win"dle*strae`\, Windlestraw \Win"dle*straw`\, n.
   (Bot.)
   A grass used for making ropes or for plaiting, esp. Agrostis
   Spica-ventis. [Prov. Eng. & Scot.] --Shelley.
   [1913 Webster]