prolificacy

from WordNet (r) 3.0 (2006)

prolificacy
    n 1: the property of producing abundantly and sustaining
         vigorous and luxuriant growth; "he praised the richness of
         the soil"; "weeds lovely in their rankness" [syn:
         {richness}, {rankness}, {prolificacy}, {fertility}]

from The Collaborative International Dictionary of English v.0.48

Prolificacy \Pro*lif"ic*a*cy\, n.
   Prolificness. [R.]
   [1913 Webster]